**1. Introduction**

Streets and their designs are essential elements of urban living in terms of walking [1–3]. Urban transportation planning has paid little attention to walking since motor vehicles became ubiquitous, but walking remains the main travel mode for the first and last miles of a trip. Beyond its transit functions, it enhances individuals' physical and mental health and the environmental, social, and economic sustainability of cities [4–7]. By considering walking, city streets might be revitalized, declining economies might be revived, and the quality of life might be improved [8–10]. Giving streets back to pedestrians is a common goal of most urban design theories [11–13].

However, cars have long been central to urban transportation planning; therefore, in many cities, streets are hostile to pedestrians. The narrow asphalt streets without sidewalks that typically develop in urban areas are the representative legacy of "automobilism" [14]; they are obvious in the dense megacities of developing countries where infrastructure cannot keep pace with population growth and in the older districts of advanced countries where organic patterns remain, such as Beijing, Ho Chi Minh City, Kyoto, and Taipei. These streets tend to be alleys, back roads, or access streets to commercial buildings in urban residential areas. They are frequently used by pedestrians, who are forced to share them with cars under dangerous conditions.

Korea is no exception to the problem. Its typical urban neighborhoods include many narrow streets without sidewalks, named *i-myeon-do-ro* (back roads) (Figure 1). These streets (less than 12 m wide) comprise about 77.1% of Seoul's total street length [15]. Because they are not wide enough and, therefore, do not have sidewalks, pedestrians share them with cars, enduring unsafe conditions. About 73.7% of Korea's pedestrian traffic accidents between 2013 and 2015 occurred on streets less than 13 m wide [16]; as of 2016, pedestrian fatalities as a share of all street fatalities constituted 40%, the highest among the 34 OECD countries [17]. Even though this might indicate a relatively high share of walking for transportation [18], these figures demonstrate the quality of the usual walking environment in Korea.

**Figure 1.** Typical *i-myeon-do-ro* in Seoul, Korea (before the project: Sanggye-ro 5-gil in Nowon-gu); *source:* © Daum Roadview (https://map.kakao.com/).

To address this problem, the Seoul city governmen<sup>t</sup> implemented Pedestrian Priority Street (PPS) projects, based on Hans Monderman's shared space approach [19,20]. The PPS uses stamped asphalt pavements of various colors and patterns, to alert drivers of theirs, and pedestrians' rights of way, and ensure safe and comfortable walking environments for pedestrians. The PPS are considered one of the government's most practical and feasible options in addressing the problems associated with narrow streets. The PPS projects are distinct in that they mainly target *organically* shared streets resulting from narrow widths. This is different from other shared space examples, such as Exhibition Road in London, which has a separate sidewalk and wide width [21]. Because the street space is limited, the PPS projects solely rely on the visual impacts of unique paving designs. However, little is known about the effects of the PPS and its design principles in Seoul.

In this context, this study investigated the effectiveness of the PPS's design strategies. We examined the influences of the various paving designs on changes in vehicle speed (objective safety), and on pedestrians' fears of possible car accidents (subjective safety). The eight PPS sites comprising nine streets in Seoul, that implemented the PPS designs in 2014 were analyzed. Video data were collected before and after implementation, and a cross-sectional questionnaire survey was conducted. We used the results to consider the potential of the PPS and policy directions, in order to enhance pedestrian safety and rights.
