How Do Urban Walking Environments Impact Pedestrians’ Experience and Psychological Health? A Systematic Review

Abstract

Daily walks are recommended for health gains, and walkable urban environments are recommended as one strategy to combat climate change. Evidence of the relationship between physical environments and psychological health is increasing. The aim of this study was to systematically review and compile evidence regarding micro-scale characteristics in urban outdoor environments that impacted pedestrian short-term experience and/or long-term psychological health. The databases ScienceDirect, Scopus, PubMed, PsychInfo, and Google Scholar were used. To explore the area, a large heterogeneity in publications was allowed; therefore, it was not possible to conduct a meta-analysis. From 63 publications, data items were extracted from full text and categorized according to the main study characteristics. Environmental characteristics impacting pedestrians psychologically were identified and categorized into themes: grey, green, blue, and white areas, and weather, temporalities, topography, person factors, and safety. Environmental factors were analyzed from the perspective of the circumplex model of human affect (negative/positive dimensions and activation/deactivation). The findings included the fact that urban pedestrians need both positively activating and deactivating (restorative) areas during walkabouts. Perceived safety is essential for experiencing the positive aspects of urban environments. Some characteristics interact differently or have different importance for health in different groups. To further develop research on pedestrian environments, psychological experiences should be included.

1. Introduction

Today, 55% of the world’s population lives in cities. In 2050, this number is expected to have increased to 68% [1]. Urban environments impact health in different ways. The physical environment can encourage walking and cycling instead of car use and has therefore been shown to be associated with reduced risks of obesity and diabetes [2]. Vegetation and green areas can impact physical health in cities [3]. For example, the prevalence of myocardial infarctions has been shown to be associated with distance to a green area. Creating and maintaining healthy urban environments is thus an increasingly important issue. Environmental psychology can help in understanding how different environments are experienced by users.

There is also increasing research evidence of the relationship between physical environments and psychological health. For example, in the short run, environments that are perceived as beautiful tend to evoke feelings of joy [4]. Other environments can induce feelings of unsafety [5] or have a restorative impact [6]. In the longer run, there is evidence of differences in the use of antidepressants in different environments [7], or in the frequency of anxiety [8]. This research area is, however, still insufficiently researched [9].

The desire to stay and move around in an environment, or to want to get away, can be the difference between a socially sustainable or an excluding and unsustainable environment. Recent research recommends 6000 steps per day in outdoor environments, in order to reach optimal health gains [10]. In the latest United Nations climate report [11], walkable urban environments are highlighted as one of the strategies to combat climate change. In the 2030 Agenda for Sustainable Development, the United Nations also highlighted the need to ‘ensure healthy lives and promote well-being for all at all ages’ in goal number three, and ‘to make cities and human settlements inclusive, safe, resilient and sustainable’ in goal number eleven [12].

Many of the literature reviews covering the association between environment and health focus on physical health. Fewer reviews exist on the associations between urban environments and psychological health, although the number has increased in recent years. In some reviews, psychological health and reactions are studied as part of general health, as for example, by Sarkar and Webster [13]. Others review psychological health specifically [14,15,16,17,18,19]. Some focus on specific groups such as children and/or adolescents [20]. In some reviews, specific parts of the environment are assessed in relation to health. Green space is reviewed in several studies [21,22]. Others have focused on green and blue spaces [23] or only blue spaces [24]. Hankey and Marshall [25] review how air pollution impacts physical and psychological health.

Hajrasoulih et al. [26] and Zumelzu and Herrmann-Lunecke [27] also include walkability as part of the equation; namely, how psychological health is impacted by different factors, including walkability. However, to the best of our knowledge, reviews where all three of these variables (urban environment, walkability/walking, and psychological health) are included seem to be scarce. Still, experiencing the urban environment while walking is different from looking out from a window, driving through the urban environment by car, or bicycling. Therefore, focusing specifically on studies that use walking as a means may add specificity to the knowledge in this important research area. Thus, the focus of the present paper is to investigate, given that we use walking as our means of transport, how the urban environment people walk in impacts them psychologically. Moreover, previous reviews have used different methods and databases. More studies are therefore needed to complement existing studies. For example, Zumelzu and Herrmann-Lunecke [27] mention the need for complementing existing studies with searches in Scopus or PubMed. Additionally, more research is needed on the micro-scale built environment, and how specific variables influence the walking experience [28].

This article is structured as follows. First, there is a theoretical background of pedestrians’ psychological experience of the physical urban environment. This is followed by a Methods section explaining how the review has been conducted. Next, the results are presented, first with an overview of the publications, and secondly a presentation of our central findings, which are then synthesized in a framework of the circumplex model of affect [29]. This is followed by a discussion of the findings in light of the circumplex model, and the study’s conclusions and suggestions for further research.

In the research field relating to walkable cities, Jane Jacobs [30] was one of the first to shed light on city development by underlining the need to connect parts of urban areas in a manner that should be diverse and moderately complex. ‘Walkability’ has been used with several different meanings, for example, with a focus on environmental features, on outcomes dependent on these features, or as a proxy for better design [31].

The circumplex model of affect [29,32] is a well-researched two-dimensional circular space where all emotions are distributed along two affective dimensions consisting of (1) valence (from pleasant to unpleasant) and (2) arousal (from activation to deactivation). In environmental research, these dimensions have been used to study affective experiences in residential areas [33] and park areas [34].

The present paper aims to systematically review and compile evidence from international empirical quantitative and qualitative studies regarding characteristics of urban environments that impact pedestrian psychological experience in the short and/or long term.

2. Materials and Methods

2.1. Search Strategy

A literature search was conducted in June and July 2022 using the databases ScienceDirect, Scopus, PubMed, PsychInfo, and Google Scholar. In Google Scholar, the first 50 hits were selected in each search, as sorted by relevance, as the total number was too high to include. For the other databases, all hits were included. The search was limited to empirical studies in English language journals. Thus, reports, literature reviews (including systematic reviews, meta-analyses, and other kinds of reviews), editorials, and both theoretical and method-based articles were excluded, as well as books and conference papers (

Table 1. Selection criteria used in the systematic review.

Category	Inclusion Criteria	Exclusion Criteria
Population	Defined as adults in the study	Defined as children in the study.
Exposure	Association between (a) micro-scale urban outdoor environment, (b) pedestrian, and (c) psychological health.	Meso- and macro-scale environments. Lack of a, b, or c. Studies not focused on pedestrian actual behavior. Indoor environments. Rural study areas. “View from a window” studies, cyclability or other transport studies.
Outcome	Pedestrians’ psychological experience.	Physiological outcomes only.
Study design	All types of empirical study designs, quantitative and qualitative including actual pedestrians. Different objectives, variables, methods, settings, samples, and outcomes. Clearly stated research questions, methods, sample size, and results.	Prospective studies, reviews, reports, editorial, theoretical, and method-based articles.

). No geographical boundaries were used. No time limit was used regarding publication year because of the risk of excluding potentially important older studies that could be valuable. This decision was made in light of the scarcity of research in the largely undeveloped research field investigating the impact of pedestrian perception of the environment and its psychological impact. The ‘environmental’ search words “micro scale”, “urban”, and “physical environment” were combined with the search words “walkability”, “wellbeing”, and “mental health”, respectively. For a conclusive list of search terms for each database and the number of resulting papers, see the Appendix A.

2.2. Study Selection

We used the systematic review protocol of the type detailed in the PRISMA-P Flow Diagram (Figure 1) [35]. Papers were included if they contained an association between micro-scale urban environment, walkability/walking, and some kind of psychological health measure. All three variables thus had to be included. Papers also had to clearly state the research questions and methods, and results had to be included. More specifically, an empirical paper was included if it met the following criteria:

(1)

The area investigated was (a) a microscale (b) urban outdoor environment. Indoor environments were therefore excluded. Although this article is focused on the micro level, we included certain factors that could be argued to exist on a mesoscale level, such as distance and density. However, from a pedestrian perspective, a dense environment is apparent even on a micro-scale level (Table 1). Likewise, a long distance can mean a lack of a specific attribute in the micro-scale area. Thus, the attributes that a pedestrian can experience in a small (micro) area were included in the paper even if it could be experienced on a meso-scale or even a macro-scale as well. Regarding the term “urban”, we used the definitions that had been used in the articles; thus, the meaning may differ between publications. If the area was not clearly urban, it was excluded. ‘Semi-rural’ study areas were not included, for example.

(2)

The publication focused on walkability or ‘walking’ from a pedestrian’s perspective (Table 1). Therefore, all papers included in our systematic review contained human measurements (actual participants). Additionally, the number of participants must have been specified. Thus, if walkability or walking was measured in a certain paper only with other means (such as GIS), the paper was excluded. As well, ‘view from a window’ studies have been excluded, as the pedestrian perspective would then be missing. However, when typical pedestrian attributes were in focus, such as sidewalks, benches, crosswalks, and other attributes, walking was judged to be implicit, and these publications were included, even if walkability or walking was not explicit. However, papers with only “cyclability” or other kinds of transport were excluded. Instead of walkability or walking, other expressions were sometimes used in the papers, such as “pedestrians”, or “physical activity”, and such a paper was included. Discussions of wheelchair use instead of walking have also been included.

(3)

The publication focused on the impact on psychological experience or health (long and short term) in a wide sense (Table 1). Everything from ‘simple’ psychological reactions that are aroused at the moment to long-term psychiatric diagnoses have been included. The measured health variables included affect, experience, comfort, enjoyment, happiness, psychological response, mood response, satisfaction, well-being, quality of life, psychological distress, psychosocial distress, creativity, depression, anxiety, and mental health. Safety and security have been included, as well as fear. Additionally, stress-related responses such as restorativeness or tension have been included. Physiological reactions have been included when they were stress related, such as cortisol levels and heart rate.

2.3. Data Extraction

Through the database search, 1191 publications were exported to EndNote. After duplicates were removed, both researchers together screened the remaining 892 titles and/or abstracts for relevance, in accordance with inclusion criteria, and in the process discussed and refined the inclusion and exclusion criteria. In the next step, the researchers independently sorted the studies, reading them more thoroughly, excluding those that were found irrelevant according to the inclusion criteria after discussion with the other researcher. After this stage, 213 papers remained relevant. Subsequently, papers meeting the inclusion criteria were retrieved and read in full to extract findings and other key data. One article was not available in full text and was excluded. Again, papers found at this stage not to meet the inclusion criteria were excluded, resulting in a remainder of 63 relevant papers. Data were extracted using a standardized form including main findings (that were relevant to our research questions), author(s), year of publication, region, sample characteristics, methods, sample size, and data analysis. Both quantitative and qualitative designs were accepted. To explore the research area, a large heterogeneity of papers was accepted in relation to objectives, variables, methods, settings, samples, and outcomes. Therefore, conducting a meta-analysis was not possible. The flow chart of the papers retrieved is presented in Figure 1.

The study was thus conducted in five steps (c.f. [36]). (1) The questions for the review were framed, and the exact research questions were specified and set. (2) An extensive search for studies was conducted using multiple sources. Reasons for inclusion and exclusion were clearly stated and recorded. (3) Studies that fulfilled the inclusion criteria were included after intermediate judgments; independently of the method, psychological measurements had to build on subjective personal data. A decision was made that the systematic review structure was not suitable for conducting a meta-analysis depending on the heterogeneity of the publications. (4) The evidence of the main study characteristics was summarized. (5) The findings were interpreted in the light of physical and personal attributes. The physical attributes and their impact on the pedestrians’ experience were categorized in the light of the circumplex model of affect [29]. Throughout the entire process, the two researchers have been discussing concepts and making judgments. Ethical approval has not been required, because only secondary data was used. Risks of publication bias and other biases were explored.

3. Results

Of the 63 original papers, eight of them were published in Landscape and Urban Planning (

Table 2. Distribution of publications.

Journal	No. of Publications
Landscape and Urban Planning	8
Urban Forestry & Urban Greening	5
Social Science & Medicine	4
Cities	3
Health & Place	3
Journal of Environmental Psychology	3
Research in Transportation Business & Management	3
Wellbeing, Space, and Society	3
Geoforum	2
Journal of Epidemiology and Community Health	2
Science of The Total Environment	2
Travel Behaviour and Society	2
Aging & Mental Health	1
Ain Shams Engineering Journal	1
Applied Research in Quality of Life	1
BMC Public Health	1
Case Studies on Transport Policy	1
Cities & Health	1
City, Culture, and Society	1
Environment and Behavior	1
Environmental Research	1
Frontiers in Public Health	1
International Journal of Environmental Research and Public Health	1
International Journal of Sustainable Transportation	1
Journal of Applied Gerontology	1
The Journal of Mental Health Policy and Economics	1
Journal of Transport & Health	1
Journal of Transport and Land Use	1
Journal of Urban Design	1
PLOS ONE	1
Progress in Planning	1
Social Indicators Research	1
Transportation Research Part A	1
Transportation Research Part D	1
Transportation Research Procedia	1
Publications total	63

). Urban Forestry and Urban Greening had five publications, and Social Science and Medicine had four. The largest number of studies was conducted in North and South America (35%), followed by Europe (24%), Asia (22%), Oceania (16%), and Africa (3%). The United States was the country with the largest number of publications, followed by China and Australia. See

Table 3. Geographical distribution of publications.

	No. of Publications
United States	13
China	8
Australia	7
United Kingdom	6
Canada	4
Brazil	3
Japan	3
New Zealand	3
Sweden	2
Belgium	1
Chile	1
Egypt	1
Germany	1
India	1
Iran	1
Malaysia	1
Mexico	1
Netherlands	1
Norway	1
Portugal	1
Sierra Leone	1
South Korea	1
Spain	1
Switzerland	1
Total	63

for the geographical distribution of all publications. The number of publications has increased over the years, and most of them (67%) were published recently, during the years 2018–2022. The oldest publication was from 2005.

Table 4. All publications with basic data and main findings in alphabetic order.

Author, Year	Region	Respondents	N	Respondent Data Collection Methods	Sampling Method	Respondent Data Analysis	Findings
Alfonzo et al. (2008) [37]	USA, California	Parents of 3rd–5th grade students	1297	Survey	Purposive	Descriptive, multiple regression analysis	The amount of walking performed by adults in their neighborhood: the most important criteria in the physical environment, as influenced by safety levels relative to crime. Mixed-used sidewalks, public open spaces, and higher adult walking rates. More windows facing the street, more street lighting, and fewer abandoned buildings, graffiti, rundown buildings, vacant lots, and undesirable land uses have higher adult walking rates.
Ayala-Azc-árraga et al. (2019) [38]	Mexico, Mexico City	≥18 years old	338	Survey (person to person)	Convenience	Chi-square test, canonical correlation analysis.	Well-being explained by trustworthy neighbors, trustworthy visitors, and park shared with well-known people.
Bahrainy and Khosravi (2013) [39]	Iran, Hashtgerd New Town	Residents	384	Survey	Random sampling in selected clusters	Multivariate linear regression	The environment influences female residents more than male residents. Safety is the most important factor for women; for men, distance to destinations.
Barr et al. (2021) [40]	United Kingdom, Exeter	Commuters	96	Workshops, semi-structured discussions	Not specified. From previous study	Thematic analysis	Shared spaces: sites of uncertainty and conflict between different users.
Bereitschaft (2019) [41]	United States, Omaha	Residents	293	Survey	Random	Correlation, spatial point pattern test	Hotspots of walkability and creativity frequently overlapped.
Biglieri and Dean (2021) [42]	Canada, Waterloo, Ontario	57–81 years with dementia	7	Longitudinal. Go along interviews, travel diary	Not specified	Grounded theory approach, coding, peer checked. Travel diary.	Persons with dementia avoided noisy, smelly, fast-moving arterial roads, and selected instead quieter residential or mixed-use streets, even if it took longer. It was difficult for persons with dementia when the neighborhood was lacking amenities within walking distance.
Bornioli et al. (2019) [43]	United Kingdom, Bristol	Adults working or studying	398	Experiment, photo-elicited semi-structured interviews	Convenience	Multiple regression	Safety, comfort, and moderate sensory stimulation are crucial elements for the walking experience.
Brancato et al. (2022) [44]	United States	21–72 years old	202	Experiment (virtual walk)	Convenience (crowd- sourcing)	ANOVA	Pine forest walks were superior in inducing happiness in comparison with urban walks. Farm field walks were less fascinating than all other walks, including urban. Busy city center walks reduced feelings of calmness in comparison to all other walks.
Brown et al. (2007) [45]	United States, Salt Lake City	Students, trained raters	73 + 4.	Experiment	Convenience	Environmental audit, Cohen’s kappa, PCA, coefficient alpha	An area where it is possible to watch people enjoying themselves gives a positive experience. Poor aesthetics interfere with a positive walking experience (e.g., dirty spaces, dark colors, abandoned buildings, litter, graffiti). Artistry and attractiveness of shop or store windows positively experienced. Shade gives a positive walking experience.
Bustamante et al. (2022) [46]	United States, District of Columbia and Puerto Rico	≥55 years	6938	Questionnaire	Purposive convenience sampling	Thematic analysis, generalized linear models, chi-square	Depression and anxiety are inversely associated with the number of neighborhood parks.
Cambra and Moura (2020) [47]	Portugal, Lisbon	Individuals who lived in, worked in, or visited the area	802	Quasi-experiment, longitudinal survey	Not specified	T-tests	Walking experience related to sidewalk pavement quality, kiosks providing outdoor sitting places with extended working hours. Turning radius reduced to slow down turning traffic; crossing refuges enlarged.
Cao (2016) [48]	United States, Minneapolis, St Paul	Residents	1303	Survey	Stratified, random	SEM, confirmatory factor analysis	High density and poor street connectivity are detrimental to life satisfaction, but street connectivity is more influential than density.
Chan et al. (2018) [49]	China, Hong Kong	Urban park managers, local scholars, and local park users	772	Interviews and questionnaire	Stratified random	PCA, Crohnbach’s alpha	Safety and security are among the most important areas for management in parks. Natural settings such as ponds and trees are important for a pleasant feeling in parks. Soft landscape or green areas were preferred to hardware over built facilities.
Chan et al. (2021) [50]	China, Shenzhen	Residents	20	Walk-along and sedentary interviews	Purposive	Thematic analysis	Temporalities important for how a phenomenon is perceived, for example, in relation to safety.
Deng et al. (2020) [51]	China, Chengdu	Students	60	Questionnaires; Various physiological indicators	Convenience (randomization to conditions)	T-test, ANOVA. Wilcoxon signed-rank, Kruskal– Wallis.	Topography landscapes with natural mountain forest appear most restorative. Water, topography, and plants had positive restorative effects, as did bamboo forests, poetry walls, and decorative openwork windows.
Domènech-Abella et al. (2021) [52]	Belgium, Flandres	≥60 years	869	Face-to-face questionnaire (interviews)	Not specified. Subsample from previous study.	Linear regression	No significant associations between traffic density and basic service availability and mental health.
Dzyuban et al. (2022) [53]	United States, Phoenix, Arizona	Residents	14	Survey: Thermal comfort (microclimate), pleasure, and visual experience during thermal walk. GPS.	Convenience	Descriptive statistics, Spearman correlation	Changes in pleasure resulting from slight changes in microclimate conditions in streets where participants walked. Participants could sense minor changes in microclimate and perceived shade as pleasant while walking down a street.
Finlay (2018) [54]	United States, Minneapolis	Residents, 55–92 years old	125	Interviews, observation	Purposive	Thematic analysis	Snow impacted participants; for example, they expressed anxiety because of fear of slipping on ice or were afraid of getting stuck.
Finlay et al. (2015) [55]	Canada, Vancouver	Older adults	46	Sit-down interviews, walking interview	Not specified. Partly based on earlier study.	Thematic analysis	Green and blue spaces impact mental health in later life. The spaces promote mental well-being and induce feelings of renewal, restoration, and spiritual connectedness, and support social engagement.
Fleming et al. (2016) [56]	New Zealand, whole country	≥15 years	22,727	Survey	Random	Logit model estimated by maximum likelihood estimation.	When residents report that they feel unsafe in their neighborhood, psychological benefits of access to green space disappear almost entirely.
Foster et al. (2013) [57]	Australia, Perth	Residents (before and after relocation)	1159	Questionnaire (longitudinal)	Purposive (all who completed question aire from earlier study)	Linear regression	Shopping/retail land use enhances walking and paradoxically also possibly deteriorates walking by increased residents’ perceived crime risk.
Foster et al. (2015) [58]	Australia, Perth	Parents	1245	Cross-sectional study	Random, stratified	Descriptive	Neighborhood features minimizing vehicle traffic and encouraging pedestrians supported most parents’ perceptions of safe neighborhoods, regardless of socioeconomic status.
Francis et al. (2012) [59]	Australia, Perth	Residents building homes in new housing developments.	911	Survey	Not specified	Logistic regression	Odds for low psychosocial distress are higher for residents in neighborhoods with high-quality public open space (POS). POS attributes included walking paths, shade, water features, irrigated lawn, birdlife, lighting, sporting facilities, playgrounds, type of surrounding roads, and presence of nearby water. Quantity of POS has less mental health impact than quality.
Galea et al. (2005) [60]	United States, New York City	Residents ≥18 years old	1355	Telephone survey	Random	Cronbach’s alpha, multilevel hierarchical models, odds ratios	No impact on depression based on percentage of clean streets or sidewalks. A higher percentage of houses in deteriorating condition was associated with a greater likelihood of depression.
Gidlöf-Gunnarsson and Öhrström (2007) [61]	Sweden, Stock- holm, Gothen- burg	Residents exposed to high road traffic noise	500	Cross-sectional questionnaire	Not specified. Subsample from previous study	MANOVA, ANOVA, chi-square, t-tests, correlation	Better availability of nearby green areas important for well-being by reducing long-term noise annoyances and prevalence of stress-related psychosocial symptoms.
Guo et al. (2021) [62]	China, Hong Kong	Older adults	1553	Survey	Quota with stratification	SEM	Park green space positively affects mental health and subjective well-being. Vegetation-based green space negatively associated with subjective well-being. Density enhances subjective well-being in older adults. Perceived built environment and sense of community could fully explain the residential density and subjective well-being relationship. Street connectivity associated with mental health; however, inverted U-shape.
Herrmann-Lunecke et al. (2021) [63]	Chile, Santiago	Residents	120	In-depth walking interviews	Convenience	Grounded theory	The presence of trees, wide sidewalks and active uses of design features ease walking, elicit well-being and happiness. Traffic noise, motorized traffic, narrow and deteriorated sidewalks, and difficult crossings hinder walking, especially for older adults and women, causing stress, fear, and anger.
Høj et al. (2021) [64]	Canada, Montreal	Residents	929	Face-to-face questionnaire, longitudinal	Stratified	Linear growth mixture- modeling	Public open space (POS) per se did not attenuate impact of stressful events on psychological distress or independently protect against psychological distress but “greener” POS protected against rising stress in both cases.
Juntti and Lundy (2017) [65]	United Kingdom, London	Lived in local social housing or had worked there for over one year	10	Interview, visual and textual recording	Convenience	Constructivist approach, descriptive	Parks give a positive sense, for example, if offering an activity such as a basketball court, jogging, or festivals. Even small pocket green spaces are positive. Benches portrayed as enabling factors for giving positive experience.
Juntti et al. (2021) [66]	Brazil, Belo Horizonte	Residents	24	In-depth interviews, accompanied walks, “walking narrative”	Purposive	Cross-referencing, thematic analysis	Well-being is only experienced when residents feel safe in their neighborhood.
Kent et al. (2017) [67]	Australia, Sydney	Households	562	Survey	Not specified	PCA, correlation, ordered logit model, Tobit model	Aesthetics associated with subjective well-being. Aesthetics here are defined as presence of street trees and views, and evaluation of the attractiveness of buildings.
Kim et al. (2014) [68]	South Korea, Seoul	Pedestrians	28,000	Survey	Convenience	Descriptive statistics, correlations, multilevel modeling, ordinal logit, likelihood ratio	Trees associated with satisfaction, as were bus lanes, width of sidewalks, crossing signs, traffic lights, pedestrian crossings, and availability of bus stops. Intersection density had a negative effect on satisfaction as did hilly topography.
Koohsari et al. (2019) [69]	Japan, Matsudo City	Residents aged 65–84 years old	328	Questionnaire, on-sight health examination	Random	Descriptive statistics, Pearson’s correlations, Gender- stratified multivariable linear and binary logistic regression, Odd ratios (OR)	Walkable environment characterized by high population density and proximity to local destinations is supportive of better mental health among older adults, in particular women.
Kwon et al. (2019) [70]	United States, Texas/Ohio	Residents	1392	Survey	Convenience (crowd-sourcing)	SEM	Safety from crime not related to recreational well-being.
Lamour et al. (2019) [71]	Brazil, São Paulo	Pedestrians	79	Observation, survey/street/ interview	Purposive/ convenience	Not specified	Attributes related to safety and security are important (good crossing conditions, good pedestrian signage, pavement quality, secure speed limit, presence of traffic lights, street lighting, security from crime, pedestrians in the same area).
Lucchesi et al. (2021) [72]	Brazil, Sao Paolo	Young adults (18 to 29 years old), middle-aged adults-1 (30 to 45), middle- aged adults-2 (46 to 59) and older adults (60 to 70 years old)	2300	Interviews	Probabilistic, stratified	SEM, configural model, chi-square	Subjective well-being positively influenced by security in all age cohorts. Safety had the highest effect on the elderly while middle-aged people valued walkability. Younger people seemed to be least influenced by safety and walkability.
Ma et al. (2018) [73]	Australia, Sydney	Residents	562	Survey	Purpose, representative	Descriptive, SEM	Cohesive neighborhood environment associated with better mental health, better subjective well-being. The aesthetics and the social environment of the neighborhood had the strongest effects on subjective well-being.
Martens et al. (2011) [74]	Switzer- land, Zurich	General public	96	Experiment (questionnaire)	Convenience, then randomly assigned	Factor analysis, Cronbach’s alpha, ANOVA	Participants who walked in a tended forest had a stronger increase in positive affect and a stronger decrease in negative affect than those who walked in a wild forest.
Meher et al. (2021) [75]	New Zealand, Aotearoa, Auckland	Older or mobility- impaired people	62	Interviews	Purposive	Thematic	Absence of concrete sidewalks, cracks in the pavement, obstructions to public footpaths, barriers related to safety as well as overhanging tree branches and cars parked in driveways. Beautiful sights increase well-being (e.g., trees, sky, birds, and sea).
Mouratidis (2018) [76]	Norway, Oslo	≥18 years	1344	Survey, in-depth interview.	Random	SEM	Compactness positive for the number of close relationships, frequency of meeting friends and relatives, social support, opportunities to meet new people, and satisfaction with personal relationships.
Nag et al. (2020) [77]	India, Kolkata	Users	400	Surveys	Not specified	Ordered logistic regression and odds ratio analysis. Negative binomial regression	Obstructions along footpaths have negative impact on satisfaction. Important also: barrier between footpath and road, zebra crossings, footpath continuity, and lights.
Othman et al. (2021) [78]	Egypt, Alexandria	Responses from Smouha and the Northern Zone	202	Survey	Random sample and convenience	Descriptive, regression, chi-square, Mann–Whitney Test, t-test	Street linearity contributes to satisfaction, as do perpendicularity and ease of wayfinding, hierarchy of streets, continuity, connectivity, width of sidewalks, crossing signs, and traffic lights.
Ottoni et al. (2016) [79]	Canada, Vancou- ver	61–89 years	50	Semi-structured interviews	Purposive	Thematic review	For older adults, benches positively contributed to their mobility experiences by enhancing both use and enjoyment of green and blue spaces, serving as a mobility aid.
Oviedo et al. (2021) [80]	Sierra Leone, Freetown	Residents of Moyiba	38	Structured interview/questionnaire	Convenience	Descriptive	Positive for walking experience: lack of traffic, longer distance to major roads, diversity of street activities, shade, and vistas. Functioning streetlights along the footpath are important for positive walking experience and satisfaction. Benches are enabling or give a positive experience. Unpaved or damaged routes mean lower comfort. Dust or dirt, street isolation, and lack of trees are negative for the walking experience.
Park et al. (2011) [81]	Japan	Male university students with no reported history of physical or psychiatric disorders.	168	Field experiments (questionnaire, walk)	Not specified	The Steel–Dwass test, Wilcoxon rank sum test, PCA	Forest setting compared to urban setting is more enjoyable, friendly, natural, and sacred. Psychological response is also related to air temperature, relative humidity, radiant heat, and wind velocity.
Phillips et al. (2013) [82]	United Kingdom, Swansea	Older adults	44	Interviews, images, “field” visit, focus group	Purposive convenience	Cronbach alpha, PCA, content analysis	Barriers for older people in new environments include poor signage, confusing spaces, poor paving, and ‘sensory overload’, i.e., noise and complexity of the environment. Landmarks and distinctive buildings are more important than signage in navigating unfamiliar areas.
Pun et al. (2019) [83]	United States, whole country	57–85 years.	4750	Questionnaire	Not specified	Linear mixed models	Increase in roadway distance significantly associated with decrease in depressive score both directly and through loneliness.
Ram et al. (2020) [84]	United Kingdom, London East Village	Adults seeking different housing tenures	1278	Controlled prospective cohort study	Purposive	Multilevel linear regression	Closer to the nearest park, more walkable areas, better access to public transport, and measured improvements in neighborhood perceptions gave no evidence of improved mental health and well-being.
Roe et al. (2020) [85]	United States, Virginia, Rich- mond	Residents from an independent living facility for older people	11	Repeated measures, cross-over design, experiment	Purposive	T-test, descriptive analysis, multilevel random coefficient modeling	Significant positive health benefits from walking in the urban green district on emotional well-being (happiness levels) and stress physiology.
Samuelsson et al. (2018) [86]	Sweden, Stock- holm	General public	1032	Survey	Convenience	Logistic regression	Areas with proximity to major roads associated with negative experiences. There was a decline in probability of positive experiences for the first 300 m. for natural environments, while it increased after that. Natural shading by trees strongly predicted positive experiences.
Sarkar et al. (2013) [87]	United Kingdom, Wales, Caer philly	Men 65–84 years	687	Questionnaire, clinical examinations	Not specified. Based on previous study	Logistic regression	Higher degree of land-use mix associated with lower psychological distress. Diversity and many simultaneous impressions are not always positive. People living in terraced houses have reduced psychological distress compared to those living in detached houses. In hilly environments—when the variability in slope is higher, increased risk of psychological distress.
Sturm and Cohen (2014) [88]	United States, Los Angeles	Residents	1070	Survey	Stratified	Multiple regression	Residents within a short walking distance from parks (400 m) have mental health benefits, with a significant decrease over the next distance values.
Tan and Lee (2022) [89]	Malaysia, Bandar Sunway	Residents 60 years and older	250	Survey, in-depth interview	Purposive	Partial least squares structural equation modeling (PLS-SEM)	Life satisfaction is not well-related to walkability, pedestrian accessibility, and maintenance of the neighborhood.
Tang et al. (2021) [90]	China, Hong Kong	Residents, middle-aged and older adults	2247	Face-to-face interviews	Quota with stratification	Pearson correlation	Cleanliness and green spaces are associated with better mental health in older people, as are pavements, barriers between footpaths and road, zebra crossings, footpath continuity, and lights.
Tao et al. (2020) [91]	China/Beijing	Residents 18–65	1256	Survey	Stratified random	SEM	Proximity to parks as the sole indicator directly linked to mental health.
Van Dyck et al. (2015) [92]	Australia, Victoria	55–65 years	3965	Surveys	Not specified. Baseline data from previous study.	Descriptive, Pearson correlations, g multiple linear mixed models, mediation analyses	Areas pleasant to walk, those with tree shade, easy-to-walk places, and often seeing others walking supported walking, which mediated mental-health-related quality of life.
van Hoven and Meijering (2019) [93]	Netherlands, Groning- en	Older adults	7	Interviews, neighborhood walks	Convenience	Thematic analysis	For older adults, cobblestone can induce fear of lack of control. Trees can provide sun and shade making walking there pleasant. Many of the benign variables are weather-dependent.
Veitch et al. (2022) [94]	Australia, Melbourne	Participants recruited at university	20	Experimental	Oppor tunistic	ANOVA	Urban walking in comparison with green walking conditions: no statistically significant differences in changes in heart rate or cortisol in response to walking.
Vert et al. (2020) [95]	Spain, Barcelona	Adult office workers	59	Randomized crossover design	Random	Mixed-effects regression	Well-being and mood response significantly improved after subjects had been walking in blue space in comparison with resting in the control site or after walking in urban space.
Völker et al. (2018) [96]	Germany, Bielefeld, Gelsenkirchen	Residents	1041	Questionnaires.	Random	Descriptive and bivariate analysis, linear multiple regression	Blue space use increases the probability of being healthier in highly urbanized areas.
Wenjie et al. (2020) [97]	China, Beijing	Residents	4762	Questionnaire	Stratified	Multilevel-ordered logistic regression	Positive association between residential proximity to golf courses and life satisfaction. This association is more pronounced for residents living at the closest distance and, for example, golf landscape characteristics.
Witten et al. (2022) [98]	New Zealand/Aotearoa, Auckland, Mangere	Adults, children. Residents, local stakeholders.	Data collec tion 1: 1234 + 658. Data collec tion 2: 1275 + 628.	Longitudinal face-to-face survey, focus groups, go-along interviews	Random	General linear mixed modeling, thematic analysis	Results support the importance of combining traffic and personal safety as well as multiple measures when investigating pathways between active travel and the built environment.
Wu et al. (2022) [99]	China, Beijing	Residents	3495	Survey, face-to-face interviews	Stratified	Descriptive statistics, Bayesian multilevel ordered logit modeling	Mixed land use (residential, commercial, and public services) positive for life satisfaction in both residential and workplace settings.

shows all publications, together with the basic data and main findings.

3.1. Environmental Factors

3.1.1. “Grey” Areas

In the reviewed papers, there is no consensus on the impact of traffic on psychological experiences and health. Bornioli et al. [43] found motor traffic to negatively impact both affect and intentions to walk. Motorized traffic and traffic noise induced stress, fear, and anger, especially in older adults [63]. Likewise, Samuelsson et al. [86] and Oviedo et al. [80] found a lack of traffic and a longer distance to major roads to be positive for the walking experience. In a study by Cambra and Moura [47], reducing the turning radius to slow down turning traffic led to a positive influence on the walking experience, pedestrian flow, and volume. Foster et al. [58] found that neighborhood features that minimize vehicle traffic and encourage pedestrians supported parents’ perceptions of safe neighborhoods, regardless of socioeconomic status. The authors speculated that the natural surveillance in a more walkable neighborhood helped to reduce parents’ fear of strangers harming their children. Additionally, persons with dementia [42] avoided noisy, smelly, fast-moving arterial roads, and selected quieter residential or mixed-use streets to seek comfort, even if it took longer to get to a destination. Persons with dementia also avoided roundabouts and complicated or busy intersections, so they only had to pay attention to one direction of traffic at a time. An increase in roadway distance was also associated with decrease in depressive and anxiety scores, both directly and by reducing feelings of loneliness [83]. The effect on anxiety became, however, insignificant if adjusting for road traffic or noise.

Domenech-Abella et al. [52] found no significant association between traffic density and mental health. In another study, there was no relation between recreational well-being and traffic (measured as traffic safety, amount of traffic, exhaust fumes, and noise) [70]. An interaction effect was found by Gidlöf-Gunnarsson and Öhrström [61]; perceived availability of green areas decreased long-term traffic noise annoyance, noise as a neighborhood problem, and noise disturbance of outdoor stay. There were also indications that fewer residents with nearby green areas experienced stress-related symptoms. Thus, nearby green areas seemed to be a potential protective factor that could moderate the adverse impact of road traffic noise on residents.

Sidewalks and crossings impact pedestrians in different ways. The width of sidewalks can contribute both to satisfaction [68,78] and to walkability, which in turn is highly associated with creativity, according to Bereitschaft [41]. Narrow and deteriorated sidewalks and difficult crossings hinder walking, especially for older adults and women, causing stress, fear, and anger [63]. The wide sidewalks ease walking and elicit well-being and happiness in walkers in this study. A reason why women find the width of sidewalks more important than men can be, according to the authors, that women, more often than men, in Chile, where the study is conducted, perform care-taking activities such as picking up children and buying food. Pavements (together with other variables) are associated with better mental health in older people in a study by Tang et al. [90]. However, in New York City, Galea et al. [60] found no impact on depression based on percentage of clean streets or sidewalks.

Cracks in the pavement can be a matter of safety [75], and unpaved routes mean lower comfort [80]. Likewise, for older adults, cobblestone surfaces can induce a fear of lack of control [93] and cause worry about tripping on loose tiles on the sidewalk, or falling, if the surface is slippery. Likewise, Lamour et al. [71] found pavement quality to be important for safety. Severely damaged routes decrease comfort, especially during the rainy season in Sierra Leone [80]. Meher et al. [75] describe how the absence of concrete sidewalks can force people to walk in other places which may impact safety. Improving sidewalk pavement quality led to a higher positive influence on walking experience, pedestrian flow, and volume [47].

The number of intersections can impact the experience. Having to cross many intersections made pedestrians less satisfied compared to having to cross fewer intersections, as reported in a study by Kim et al. [68]. Intersection density had a negative effect on pedestrian satisfaction in both utilitarian and recreational walking. Continuity, “with one part linked to the next so that eventually any part can be reached”, was the most important quality for walkability in Bahrainy and Khosravy [39], in an environment under construction. Likewise, poor street connectivity was found to be negative for life satisfaction, and, compared to density, more influential [48]. Street connectivity was found to be associated with mental health [62]; however, the results traced an inverted U-shape, so too few or too many road intersections were associated with lower mental health. Street linearity [78] contributed the most to the satisfaction level when walking, as did perpendicularity and easiness of wayfinding, hierarchy of streets, continuity, and connectivity. Ma et al. [73] found that a cohesive neighborhood environment is associated with less transport disadvantages, better mental health, and better subjective well-being.

To be able to cross the street safely and conveniently can have a psychological impact on pedestrians. Kim et al. [68] found availability of pedestrian crossings to be associated with higher satisfaction. The same result was found also by Nag et al. [77] and Tang et al. [90]. Crossing signs and traffic lights can contribute to satisfaction [78]. It is important for safety to have good crossing conditions, good pedestrian signage, good traffic lights (for example, waiting times), and a secure speed limit [71]. However, Tan and Lee [89] found no association between life satisfaction and ‘pedestrian connectivity’ in which crosswalks and pedestrian signals were part of the measure (together with lighting and separate sidewalks). In this case, the authors comment on the fact that their findings are contradictory to those of earlier studies.

In a study by Nag et al. [77], the presence of obstructions along the footpath has a negative strong impact on satisfaction of pedestrian facilities. Obstructions to public footpaths were also found to be a barrier related to safety [75], as were overhanging tree branches and cars carelessly parked in driveways. Barriers between footpath and road can be important for satisfaction [77] as can a continuous footpath from origin to destination.

Shared spaces are in focus in some of the publications. Barr et al. [40] investigated walkers and other travel-mode users in an interview study. Shared spaces showed a likelihood of inflicting uncertainty and conflict between different road users through lack of regulation, diversity, and relative novelty. Streets were found to represent places of exclusion for the people who live along them and want to use them by walking or cycling. (”I know I’m a pedestrian and therefore the lowest of the low in terms of the pecking order.”) Kim et al. [68] found dedicated bus lanes to be associated with more satisfaction for both utilitarian and recreational pedestrians.

A diversity of street activities is often positive for the walking experience while street isolation is negative [80]. Local shops are associated with well-being [63]. To see other pedestrians in the same area is important for safety; therefore, people can take a detour to avoid emptiness [71]. Mixed land use (residential, commercial, and public services) was found to be positive for life satisfaction in both residential and workplace settings in a study by Wu et al. [99]. Areas with more windows facing the street have higher walking rates because of higher safety [37]. Land use diversity and commercial ground-floor façades influence walkability positively [71]. Lively urban environments with shopping and entertainment amenities together with residences were found to be walkable, which in turn was associated with creativity. Unique architecture is also directly associated with creativity [41]. Similarly, an area where it is possible to watch people enjoying themselves can give a positive experience [45]. Thus, playgrounds can be associated with lower psychological distress [59]. A higher degree of land-use mix is associated with lower psychological distress [87] and higher local-level street-network accessibility. However, diversity and many simultaneous impressions are not always positive. Bornioli et al. [43] found that city busyness (the feeling that “the city never seems to rest”) was perceived negatively. A similar result was found in older people by van Hoven and Meijering [93]; busy streets deterred the participants from making trips further away because of fear of lack of control.

Barriers for older people in new environments include poor signage, confusing spaces, poor paving, and ‘sensory overload’, for example, noise and complexity of the environment [82]. In this study, landmarks and distinctive buildings were more important for the walkers than was signage, when navigating unfamiliar areas. Small changes, such as indicating the distance to an area on clearly marked signage, are important.

Poor aesthetics also interfere with a positive walking experience. Ma et al. [73] found the aesthetics and the social environment of the neighborhood to have the strongest effect on the inhabitants’ subjective well-being. Poor aesthetics can relate to spaces that are dirty or have dark colors, abandoned buildings, litter, or graffiti [45], which is perceived as lack of care. Abandoned buildings, graffiti, run-down buildings, and vacant lots in the area produce lower walking rates due to unsafety, especially for recreational walking [37]. Oviedo et al. [80] also found dust or dirt to give a negative walking experience.

The same was found in Kwon et al. [70]; attractiveness and maintenance are related to recreational well-being. Cleanliness and upkeep are therefore positive [45]. Cleanliness is also associated with better mental health [90]. A higher percentage of houses in deteriorating condition was associated with a greater likelihood of depression [60]. In this area in New York City, the number of fires in the neighborhood was another variable positively associated with depression. However, Tan and Lee [89] found no association between maintenance levels and life satisfaction provided by the neighborhood in older persons.

Beautiful sights can increase well-being [75]. These can include trees, sky, birds, and sea. Francis et al. [59] also found birdlife to be associated with lower psychosocial distress. Likewise, in Kent et al. [67], aesthetics is associated with subjective well-being, (aesthetics is here defined as presence of street trees and views and perceived attractiveness of buildings). Additionally, in Oviedo et al., view increases the positive experience of walking [80]. Specifically, artistry and attractiveness of shop or store windows is positively experienced [45].

Being close to services and amenities has positive psychological implications in some of the publications. For example, the availability of bus stops is associated with higher pedestrian satisfaction [68]. Additionally, Kwon et al. [70] found a relationship between access to services and recreational well-being. When kiosks offering drinks and light meals were placed providing outdoor sitting places with extended working hours it led to a positive influence on the walking experience, pedestrian flow, and volume [47]. For persons with dementia, difficulties are encountered when the neighborhood is lacking amenities within walking distance, so, for this group, it is important as well [42]. Other amenities such as benches are portrayed as enabling factors or as giving a positive experience [45,65,80]. For older adults, benches positively contribute to their mobility experiences by enhancing both use and enjoyment of green and blue spaces, serving as a mobility aid, and contributing to social cohesion and social capital [79]. Gou et al. [57] found the availability of health facilities to enhance subjective well-being in older adults through a sense of community. However, the results also indicate that too many health services in the immediate area may have a negative impact on emotion, possibly because of negative associations with hospitals or clinics.

All publications concur in not finding a psychological impact of nearby services. Domenech-Abella et al. [52] found that basic service availability and mental health have no significant association. Likewise, Tan and Lee [89] concluded that life satisfaction was not significantly related to having basic services close to one’s home, even if shopping and shopping centers contributed to physical fitness, as walking to the store was the main form of physical activity for respondents (who, in this study, were older people). Shopping/retail land use enhances walking levels but paradoxically also possibly deteriorates walking levels by increased perceived crime risk [57]. Ram et al. [84] found that moving to an area with better access to public transport and other services did not improve mental health and well-being. The authors recommend robust study designs for the further examination of this research area, as many characteristics can bias the results.

The psychological impact of density also varies. Some publications have found positive psychological associations with density. Mouratidis [76] found compactness to be positive for the number of close relationships, frequency of meeting friends and relatives, social support, opportunities to meet new people, and satisfaction with personal relationships. Sarkar et al. [87] found people who lived a little closer together, in terraced houses instead of detached houses, to have reduced psychological distress. Guo et al. [57] found density to enhance subjective well-being in older adults through “age-friendliness”, which concerns buildings and outdoor spaces. The perceived built environment and sense of community could fully explain the relationship between residential density and subjective well-being.

Likewise, in a study by Koohsari et al. [69] on older adults, a walkable environment was an environment with a high population density and proximate local destinations. Additionally, such environments were more supportive of mental health, especially for women. Contrarily, Cao [48] found high density to be detrimental to life quality in Minneapolis–St Paul. Possible reasons proposed by the author were crowdedness, traffic congestion, pollution, noise, and crime. As well, Samuelsson et al. [86] did find density, when measured as the number of the mixture of residents living in a specific area and working population, to have a statistically weak effect on people’s negative experiences when they were in that area. Nonetheless, there was a large negative effect in areas with working populations only.

3.1.2. Green Areas

Several publications focus on the psychological impact of green areas, and the impact is often positive. Natural sights are related to life satisfaction [89]. Forest settings, compared to urban settings, are perceived as being significantly more enjoyable, friendly, natural, and sacred [81]. Brancato et al. [44] found that the physical environment influences affect and perceived restoration; pine forest walks were superior, compared to urban walks, in inducing happiness. Farm field walks were, however, less fascinating than all walks including urban. Busy city center walks reduced feelings of calmness in comparison to all other walks. Contrastingly, Veitch et al. [94] compared urban walking with green walking conditions and found no significant differences in changes in heart rate or cortisol in response to walking. Høj et al. [64] found that greener public open spaces protected against rising distress, both directly and through stress-buffering mechanisms. Open space per se did, however, not attenuate the impact of psychological distress. Roe et al. [85] found health benefits from walking in urban green districts. Here, health benefits were measured as increased happiness and lower stress.

In a study by Tang et al. [90], green spaces were associated with better mental health for older people. Likewise, Wu et al. [99] found greenness to significantly enhance the respondents’ life satisfaction; however, this was only at residential locations. At workplaces, it reduced life satisfaction. A possible explanation highlighted by the authors is that, at the workplace, the respondents might not be able to enjoy greenness, and that shops and restaurants are more important. Additionally, workplaces with green space may be located in more peripheral areas lacking preferred services. The authors also found a significantly increased life satisfaction at workplaces if mixed land use and greenness co-existed. Mixed land use could also moderate and decrease the negative impacts of greenness on life satisfaction at workplace settings.

In another study, access to green space was associated with life satisfaction, but only when residents felt safe in their neighborhood [56]. The same was found by Juntti et al. [66]. They concluded that well-being was only experienced when residents felt safe in their neighborhood. If they felt unsafe, the access to green areas was perceived to be limited and the positive effect vanished almost entirely. Ayala-Azcárraga et al. [38] found that well-being in parks is explained by trustworthy neighbors and park visitors and the fact that the park is shared with well-known people. Fleming et al. [56] point out that “given the considerable level of public investment in providing and maintaining green space, there is a clear need to address fear of crime in the neighborhood to ensure that the full benefits of policies directed at promoting the use of neighborhood green space for health and well-being can be realized”.

Parks, in specific, are studied in several papers and are often found to have a positive psychological impact. Proximity to parks was found to be positively associated with mental health by Tao et al. [91]. Likewise, Bustamante et al. [46] found depression and anxiety to be inversely associated with the number of neighborhood parks. Additionally, Ayala-Azcárraga et al. [38] found a lower distance to a park to be associated with well-being. Wenjie et al. [97] found a positive association between residential proximity (measured as walking distance) to golf courses and life satisfaction. This association was more pronounced for residents living at the closest distance and if the golf course was larger. Likewise, residents within a short walking distance from parks (400 m) were found to have mental health benefits, with a significant decrease occurring with increased distances [88]; even small pocket green spaces were perceived as positive. However, in some studies, there were no benefits in being close to a green area, or a larger distance was preferred. Participants who moved closer to a park (as well as closer to services) did not achieve better mental health or well-being [84]. Samuelsson et al. [86], found that there was a decline in the probability of positive experiences for the first 300 m for natural environments, with an increase after that. Thus, the probabilities of positive experiences were higher in remote natural environments. This was hypothesized to be because close green areas become an everyday experience, while a more remote environment can provide a more intense experience. Guo et al. [57] have compared parks with other kinds of green space and found parks to positively affect mental health and subjective well-being, while vegetation-based green space was negatively associated with subjective well-being. Vegetation green space refers to grasslands, woodlands, and shrublands. A possible reason here is, according to the authors, that people who live in more natural green spaces may feel isolated.

Some of the publications focus on different park interiors. Important items for a pleasant feeling in parks are natural settings such as ponds and trees [49]. Soft landscape or green areas were preferred to hardware over built facilities. However, in an interview study by Juntti and Lundi [65], parks were found to give a positive sense if they offered an activity, such as a basketball court, jogging, or where festivals were arranged. Deng [51] found that, when different kinds of park landscapes were compared in relation to restorativeness, mountain forests had the most restorative effect. Water and plants were perceived to be restorative elements, and bamboo forest, poetry walls, and decorative openwork windows were restorative components.

Other kinds of green space include lawns. These were associated with lower psychological distress in a study by Francis et al. [59]. Different kinds of forests have also been studied. Martens et al. [74], in Switzerland, found that participants who walked in a tended forest had a stronger increase in positive affect and a stronger decrease in negative affect than those who walked in a wild forest. The positive affect consisted of a good mood and calmness. Negative affect included depression and anger. However, there was no difference in “activation” or “arousal” between the conditions. Additionally, there was, surprisingly, no difference in attractiveness between the conditions, even though the affect differed. As well, there was no effect of attractiveness on well-being.

The presence of trees is often found to be psychologically positive for pedestrians, whether they are part of a larger green area or standing along a street. They elicit well-being and happiness [63], and satisfaction for both utilitarian and recreational walkers [68]. A lack of trees is negative for the walking experience [80]. Shade gives a positive walking experience in several publications [45,80]. Trees can provide both sun and shade, which made walking there a pleasant experience for older adults interviewed by van Hoven and Meijering [93]. Although trees are often found to be positive in urban environments, the species of the trees can matter. For example, in a Maori sample in New Zealand, older people would prefer native trees over new “exotic” trees that later blocked the view [75]. Samuelsson et al. [86] also found that natural shading by trees strongly predicted positive experiences. Van Dyck et al. [92] found that good possibilities for physical activity in a neighborhood in which shade from trees was an element that supported walking, and that the walking mediated quality of life.

3.1.3. Blue Areas

A few publications focus on water in urban areas. As with the green areas, the blue areas are generally perceived as positive. Finlay et al. [55] found that both green and blue spaces can have an impact on mental health in later life and can motivate participants to exercise, find fresh air, and enjoy the surroundings. The spaces promote mental well-being and induce feelings of renewal, restoration, and spiritual connectedness, as well as supporting social engagement. The appreciation of different green and blue environments evokes, however, different reactions in different persons in the study, ranging from none to enjoyment. Perceived safety, accessibility, and personal perception complicate the relationships. Francis et al. [59] found water features to be associated with lower level of psychological distress. Likewise, Völker et al. [96] found that a higher frequency of use of blue space is associated with higher mental health, and Vert et al. [95] found that well-being and mood response were significantly improved after subjects had been walking in blue space, in comparison with resting in the control site or after walking in urban space. Even wading pools are liked in highly walkable areas [45]. However, in a study by Samuelsson et al. [86], water had only a statistically weak relationship to the experience. In an interview study, blue space was perceived to be soothing and calming [65]; however, it could also be perceived negatively: “some people throw rubbish, people do that with water, they just throw things”. In such cases, the blue space was experienced as an environmental disadvantage. If a water reservoir were not maintained well, it could be a place to avoid.

3.1.4. White Areas, Weather, and Temperature

Much of what is perceived as benign to psychological health is dependent on the weather. An older person may feel independent and “well” in one context, for example, on a good-weather day when they can walk to the local store; however, in snow or rain, they may feel more dependent, fragile, “old”, and even excluded [93]. For example, benches that normally made long walks possible were not perceived to be usable in rain or snow. During winter, ice and snow change the urban environment, and therefore also change pedestrians’ experiences. In a paper by Finlay [54], participants expressed anxiety because of a fear of slipping on ice. They were also afraid of getting stuck. Moreover, getting snow in the eyes or “trying to cross an intersection in knee-deep snow” could make people uncomfortable and unhappy. People also felt isolated when they could not be outside as much, making them feel bored. Dzyuban et al. [53] found changes in pleasure resulting from only slight changes in microclimate conditions in streets where participants walked, indicating that participants can sense minor changes in microclimate. They perceived shade as pleasant, when walking down a street. Park et al. [81] showed in both urban and forest settings that the psychological response “sense of enjoyable and friendly” was positively related to air temperature, relative humidity, radiant heat, and wind velocity when temperatures were around 20 degrees Celsius.

3.1.5. Topography

When the topography is hilly, both utilitarian and recreational pedestrians tended to be less satisfied [68]. The same was found by Sarkar [87] in hilly environments—when the variability in slope is higher, there was an increased risk of psychological distress.

3.2. Temporalities

The same feature in the physical environment can be perceived in different ways depending on the time of day. A point of commercial activity on the street can be perceived as an obstacle in the morning rush hour, while, late at night, it might be seen as an island of safety [50]. Urban greenery, such as the shade of trees on the footpaths during high-temperature summers, is appreciated, but at night these trees can block the streetlights, making the street unsafe. Street lighting is important for safety [37,71,77] and for a positive walking experience [80], and also positive for satisfaction for recreational walkers [68] and and for lower psychological distress [59].

Also, knowing that something is only temporary can have psychological impact. Obstructions to walking due to construction works and unregulated commercial activities were viewed more optimistically, as they were temporary and would diminish in the future [50]. In this case, the participants anticipated that their neighborhood would become a better place to live.

3.3. Person Factors

Due to individual differences, the same physical environment can be perceived in different ways by different persons and induce different reactions. A person who is alert after a good night’s sleep, could, for example, experience an environment differently than would a tired person. Martens et al. [74] studied how fatigue would impact the experience of a walk in the forest in the morning, when the participants were more activated (felt less fatigue), and in the afternoon. The result showed that affect and arousal did not differ significantly. Thus, fatigue did not impact affect and arousal; exposure to nature did not have a more positive effect on a fatigued person.

The purpose of walking is of importance for psychological impact. In a study by Kim et al. [68] utilitarian pedestrians tended to be more satisfied if they walked alone than if they were accompanied by someone. Additionally, it was more satisfactory to walk familiar streets than unfamiliar streets. Moreover, senior pedestrians were more satisfied than younger pedestrians. These associations were not significant for recreational walkers.

Safety

Safety is often found to be important for how an environment is experienced. Incorporating CPTED (crime prevention through environmental design) principles in a neighborhood can support perceptions of safety [98]. The authors stress the importance of combining traffic and personal safety. Lamour et al. [71] found that attributes related to safety and security were the most important attributes for pedestrians. Additionally, Chan et al. (2018) [49] found safety and security to be among the most important factors for management in parks. In Alfonzo et al. [37], safety was the most important characteristic, both for recreational and destination walking. In Meher et al. [75], risk and danger impact well-being (e.g., crossing roads or, for older adults, having to use novel technologies such as a swipe card to access public transport). Lucchesi et al. [72] found that subjective well-being was positively influenced by security and walkability in all age cohorts. Safety had the highest effect on elderly people, while middle-aged people valued walkability. Younger people seemed to be least influenced by the factors of safety and walkability. In a study by Bahrainy and Khosravy [39], the environment influenced female residents more than it did male residents. Safety was the most important factor for women, while for men, distance to destinations was the most important factor. However, in a study by Kwon et al. [70], safety from crime was not related to recreational well-being. Foster et al. [58] suggest that, to improve the well-being of a population through urban strategies, people’s perceptions of safety are important matters to focus on. The quality of public open space has a larger impact on mental health than does the quantity, according to Francis et al. [59].

Hence, the results show that the physical environment is important for pedestrians’ psychological well-being. The physical environment might add, beyond the psychological health effect of the actual walking steps taken (i.e., the number of steps taken during a walk; 6000 steps is presently considered a health-beneficial amount, [10]), effects that promote restorative and pleasant deactivation, activating excitement and happiness, or, instead, depending on the physical setting, fear, stress, and helplessness, all of which add to the walking experience. It is not hard to think that the feeling induced in the pedestrian is an important dimension promoting or inhibiting future walking behavior. Figure 2 shows the circumplex model of affect [29,32] the two affective dimensions, valence (from pleasant to unpleasant) and arousal (from activation to deactivation).

4. Discussion

The present paper aimed to systematically review and compile evidence from international empirical studies regarding characteristics of urban environments that impact pedestrians’ experience or psychological health.

The reviewed publications support associations between characteristics in the physical environment and psychological impacts on pedestrians. The results indicate that ideal urban environments need to offer both activating and deactivating characteristics, as long as they are perceived positively. However, negatively activating or deactivating environments can be detrimental to people’s psychological health.

Being able to move around in the environment is essential. Therefore, in the reviewed publications, several of the characteristics that impact pedestrians psychologically relate to accessibility. Additionally, several of the reviewed studies find safety to be an important prerequisite for being able to enjoy the physical environment. This can relate to safety from crime or traffic, but also to safety from accidents, such as slipping and falling. Although most publications focus on what we can see, and visible elements such as graffiti, benches, or trees, some also point out characteristics in the environment that are experienced by other senses. Hearing (e.g., noise), smell (e.g., exhaust fumes), and tactile perception (e.g., comfortable temperature because of shade, or unevenness in pavements that has a negative impact on balance, especially for the elderly) are also important aspects of how we experience the environment. Thus, it is experienced with all our senses. Below, we discuss matters of accessibility, safety, and sensory perceptions experienced by urban pedestrians, in the dimensions of positive and negative psychological impact from the surrounding walking environment. Additionally, the environment impacts different groups in different ways, for example, women, elderly people, men, and younger people. This is discussed below in the light of the circumplex model of affect [29,32].

Aspects of accessibility are considered important in many of the reviewed publications. A lack of obstructions along the footpath makes the environment more accessible. For example, sidewalks that are wide, even, and not slippery, and streets that are easy to cross and moderately complex, with amenities such as benches, are generally experienced positively, while the opposite can give rise to unpleasant, stressful experiences. Generally, mixed land use with proximity to services, residential buildings, and workplaces is positively experienced by pedestrians. Amenities that are low-cost or free can increase the positive experience. However, in some of the studies, accessibility is not found to have a positive psychological impact. One reason is that a highly accessible place attracts a wide range of people, including some who conduct unwanted activities, such as criminal behaviors. Alternatively, the place can be perceived to have a high crime risk regardless if it is true or not. Likewise, a high density, which could indicate accessibility by proximity, can also imply crowdedness, traffic congestion, pollution, and noise. A distinction can be made between “formal” versus “psychological” accessibility [100] (p. 52). If there is formal accessibility (e.g., the sidewalk is made according to the national requirements) but not psychological accessibility (e.g., it does not feel safe to walk on the sidewalk because of criminality), people will avoid it.

Micro-scale characteristics that together make the walk seamless are positively experienced, not only for accessibility but also for safety. Diversity of street activities and land use, together with “eyes on the street”, counteracts isolation and is often found to be important for perceived safety, which is in line with previous research e.g., [101]. Therefore, a lack of windows facing the street can give a feeling of being alone. Thus, actions that create more activity in urban environments can improve safety from crime, while emptiness can induce unsafety. However, other persons present are positive, as long as they behave according to the norm [102], while people who behave in a norm-violating way can be perceived as a threat [103]. Graffiti and rubbish might be associated with such behavior in the present studies, while abandoned or run-down buildings and vacant lots can be interpreted as signs that the place is not cared for. Quality lighting at night is important. However, a fishbowl effect can be perceived as unsafe, that is, when a person is seen by others but cannot see others [104]. However, the included papers also show that different kinds of unsafety must be distinguished; traffic safety needs actions different from those regarding fear of crime, or fear of accidents, such as fear of falling.

Visual perceptions in urban environments are more researched than are other sensory perceptions in relation to psychological impact. Thus, in the present publications, most of the characteristics studied are experienced with our vision. The included papers show that visual urban characteristics can be both positively activating (e.g., viewing unique architecture) as well as deactivating and restoring (e.g., viewing green and blue spaces); see Figure 2. This is in line with previous studies. Green space has been found, in several studies, to have a restorative impact, e.g., [21,22]. The same has been found for blue spaces, but even streets can be made restorative [6].

It is clear, from the present studies, that beautiful sights, such as the sea, sky, or birds can increase well-being and be restorative. Previous studies find that environments that we (visually) perceive as beautiful tend to evoke feelings of joy [4] and thus relate to pleasant activation (Figure 2). In a large study, aesthetic visual attractiveness was ranked as even more important than both education and the feeling of safety [105]. Only the range of activities and social openness towards different types of residents were perceived as more important. The present papers also show that the sight of certain environmental characteristics can induce unpleasant activation, for example, graffiti, or unpleasant deactivation, for example, seeing houses deteriorate (Figure 2). This is also well-known from earlier research [106]. The broken-windows theory [107] suggests that visible signs of civil disorder encourage further disorder and crime. Thus, keeping environments neat can have a positive impact on pedestrians. The desire to stay and move around in an environment, or to want to get away, can be the difference between a socially sustainable and an excluding and unsustainable environment.

Referencing the auditive, olfactory, and tactile impact on pedestrians’ experience, we have found less research in our present publications. This indicates that these should be prioritized for further research, since the few extant studies still show an impact on pedestrians’ psychological health. For example, several articles in our results consider motor traffic and the noise connected to high-speed heavy traffic as activating negatively, giving rise to stress, fear, and anger (Figure 2). Additionally, smell, slippery surfaces, and the tactile sense from temperature are considered important matters in the publications.

In the present studies, it is apparent that unsafety is negatively activating pedestrians’ affect (Figure 2) and that safety can be a prerequisite for even being able to experience other characteristics as positive. Associations between urban environments and pedestrians’ experiences often include complex interactions. Safety clearly interacts with other variables, and if the environment is not perceived to be safe, it can eliminate the perception of other factors. For example, even though green areas are generally found to have a positive impact on people in several of the studies, the positive impact is only achievable if the environment is perceived to be safe. Thus, green spaces per se are not enough; it depends on how they are perceived. CPTED (crime prevention through environmental design) [108,109] states that natural surveillance, visual guidelines, spatial qualities, maintenance, and lighting are important for crime reduction. These factors have also been shown to increase perceived safety [110], and are therefore being implemented in some environments.

Safety is also, to a high extent, a matter of temporal aspects. Day and night are often experienced in different ways, with nighttime usually perceived to be more unsafe. Another temporal aspect is the season, such as winter compared to summer. Ice and snow can change the experience of the environment, and more research is needed as to winter landscapes.

Also, the present papers show that an environment may be perceived differently by different groups of pedestrians. Women are generally more sensitive to the perception of unsafety as to crime than are, for example, middle-aged men; this is generally found to be the case, and is also established in the previous research [111]. This is especially apparent at night, and thus also interacts with temporal aspects. Safety is therefore an important issue relative to psychological well-being in pedestrian environments. Future studies should investigate in more detail how the feeling of unsafety can distort perceptions of other aspects of the environment by, for example, misinterpreting shapes in the dark or not being able to see the beauty of a view that can be experienced when in another mood.

Several of the publications focus on older persons. As the percentage of older persons is increasing in many countries, cities will increasingly need to consider older persons as pedestrians. The elderly can be more sensitive to perceptions of unsafety, not only as to crime, but also as to accidents regarding, for example, uneven sidewalk surfaces and icy and slippery surfaces. The temperature and its consequences can thus be especially important for specific groups such as the elderly. Too much complexity can produce a cognitive overload in elderly persons with the beginning of dementia. In the present papers, even though diversity is generally found to be positively experienced, it is also clear that diversity, with many simultaneous impressions, can be too high. Too high a complexity with low legibility can create negative arousal, an effect also found in healthy pedestrians [33]. The feeling of personal control in the physical environment is important, and a lack of control is also linked to helplessness and psychological distress [112]. Improved knowledge of the elements that lead to a lack of control, and for whom and when this is the case, is therefore important from a health perspective. How can the feeling of control be increased in ‘messy’ environments?

Also, older persons can be more sensitive to topography. A hilly environment can make a walking route inaccessible or demand extra requirements such as a close distance between benches to give the possibility of a rest. Benches are mentioned, especially in the papers that focus on older people. Although different groups have different needs, public space is often designed for the average user [113]. However, benches and other amenities can also be a way of creating more activity and making people of all ages feel more included, instead of signaling that users should not stay and linger in the place [113]. More research is needed on older persons’ needs in the urban environment, and ‘vulnerable’ groups such as the elderly should be included in relevant planning. Temporal differences should be considered for facilitating healthy aging.

In the present publications, shopping malls have a positive impact on the elderly and solve the problem of uneven and icy surfaces in the outside environment. The shopping malls also have a balanced climate, good lighting, access to shops and foods, and plenty of benches and toilets. On the other hand, the shopping malls might impoverish the ‘open’ and around-the-clock urban environment, reducing the mixed land use in the rest of the urban setting, especially if they are not integrated well or are placed at a long distance from where people live and work. People with cars are then prioritized, and others are more excluded from the setting, also entailing negative climate consequences. If the open urban environment is impoverished, with fewer shops, cafés, and restaurants, there might be fewer ‘eyes on the street,’ which might reduce the feeling of safety from crime, especially for vulnerable groups. It seems as if the smaller malls rather add to the mixed land use than ‘take’ from the open urban environment.

In the present review, a place found to be familiar I therefore more pleasant. This is in line with previous research [114,115]. However, environmental preferences would probably also be influenced by the pedestrians’ current life situations and/or the situation in the walking moment. For example, could it be that younger persons seek, to a higher extent, unfamiliar and activating environments, while elderly persons more often tend to seek familiar, restorative environments? Additionally, the purpose of walking can influence preferences, for example, if the purpose is to find a restaurant for lunch during the limited lunch hour, if it is a means of transportation to work, or if the purpose is purely recreational.

There is no consensus on how motor traffic impacts people psychologically, although traffic is mostly perceived to be negative in the present studies, in line with earlier research; see, for example, [28]. However, the results indicate that motor traffic interacts with speed. If speed is reduced, the negative effects of noise and unsafety are reduced. Thus, more areas with driving conducted in low gear could be psychologically positive for pedestrians. Additionally, with a growing number of electric cars, noise from speed might be a lesser problem in the future. Moreover, one of the present papers finds that, even if noise itself is not lowered, access to greenery can make the noise less disturbing. As well, cars per se are not necessarily negative for pedestrians and the walking experience, as they can add to a feeling of safety, with more eyes on the streets, as long as the speed is low. Even if there is a large body of research on the impacts of motor traffic, further research is needed on the impact of traffic on pedestrians’ experience and how it interacts with other variables.

The results in the present study indicate that a truly walkable urban environment that adds to the pedestrians’ well-being is dependent on many variables. The focus has been on how people feel when they walk and the associated long-term psychological consequences. The results from the present papers have been categorized, first according to aspects of the urban environment a pedestrian can meet (grey, green, blue, and white areas and topography) as well as weather/temperature, person factors, and safety. The results were then viewed in the light of the circumplex model of affect [29,32], considering ranges from activation to deactivation and from pleasant to unpleasant. Findings show that active psychological health promotion for pedestrians needs to include a variety of restorative pleasantly deactivating and pleasantly activating environments and reduce the negative affects. Here, more research is needed on the micro-scale built environment, how specific variables are influential for the walking experience [28], and how these variables interact.

The United Nations has highlighted the need to ensure healthy lives and promote well-being for all at all ages (goal number 3) and to make cities and human settlements inclusive, safe, resilient, and sustainable (goal number 11) [12]. From the present publications, it is clear that the physical environment impacts people’s psychological health. In some cases, serious diagnoses such as depression are associated with environmental features such as deteriorated buildings. It is, however, important to remember that these results are generally correlational, and that many variables can have an impact, as these interactions are complex. This research area is, however, still insufficiently researched [9]. More research on underlying mechanisms is therefore needed.

Different research methods have been used in the papers, and this might be one of the reasons that different results have been found. Another reason might be the geographical spread of the research. Most of the included publications have been conducted in industrialized countries. Developing countries are thus less represented and should be more researched. Some findings might not be generalizable between countries. The included papers come from a range of different disciplines. Different groups of pedestrians have also been included, and the sample sizes vary. Additionally, the results are dependent on many interacting variables. For the present systematic review, there is also a possibility of publication bias, specifically, that relevant publications may not have been found. Additionally, the present study was not registered in the PROSPERO database for systematic reviews, as specified in PRISMA 2020 checklist [35]. A registration would have added transparency to the review process. Moreover, we have not used a risk assessment tool for bias to evaluate the included studies in the review. A strength is, however, that the researchers have actively worked together throughout the process and discussed every arising question, reaching a consensus, for example, as to inclusion and exclusion of publications and other issues that have come up. The present article discusses in detail the theoretical findings, but it is limited in providing suggestions as to potential changes in practice. Interventions may not be generalizable to all urban environments or all groups of users. Therefore, before making practical suggestions, it is essential to consider the local context and the mechanisms in the physical environment that give people positive versus negative experiences when walking. Who is walking, when are they walking, what is the reason for walking, and how is walking facilitated or constrained? However, ensuring safety is of paramount importance, otherwise, environments cannot be perceived positively. Moreover, temperature and temporal variations should not be forgotten (for example, day versus night or summer versus winter). It is also important to consider individual differences, especially vulnerable groups, in planning. More research on underlying mechanisms of psychological short-term and long-term effects of environments is needed, and interaction effects need to be studied. Finally, more research on the micro-scale level is needed, and specifically as to how it impacts the walking experience.

5. Conclusions

In the present paper, we conclude that people need both positively activating and deactivating (restorative) areas in the urban environment. As more people are moving into cities, we need to create environments that are positively activating and others that are restorative, and minimize environments that have a negative psychological impacts on pedestrians. The experience before, during, and after walking is important for choosing how to move in the urban environment and can impact long-term psychological health. To further develop the area of pedestrian environments and walkability, psychological experiences should therefore be included. The included papers show that perceived safety is essential for experiencing the positive aspects of urban environments, and that it is thus a prerequisite for well-being in these areas. The results also show that there are complex interactions in environmental, individual, and temporal variables that need to be considered in research and practice. The features that have a general positive impact should be preserved and multiplied in the urban environment. This will enhance walking and mental health for people. To bridge the gap between research and practice, different citizen groups should be represented in law, policies, and practice when planning or redesigning urban areas to ensure that a beneficial environment is accessible for all groups.