**2. Literature Review**

#### *2.1. Night Tourism*

Night Tourism—tourism that occurs during the night—has made a big wave in the international tourism market. In 2019, the Union Minister of State for Tourism and Culture of India emphasized 'night tourism' and they opened their important monuments until late in the night for visitors [17]. Also, the Chinese government regarded night tourism as a vast opportunity for new growth and made great efforts to boost it [18]. However, although various studies have spotlighted night tourism since the early 21st century, there is no unified definition of "night tourism" yet, instead only a main debate focused on the scope of 'night' exists [13]. Night tourism can be considered as a simple extension of tourism activities from daytime tourism activities [19]. In other words, night tourism should be characterized in that the night itself is the core attractive attribute [14]. In short, night tourism can be referred to any kind of tourism activity that occurs between sunset and sunrise.

Night tourism can be composed of various programs. Tong [20] divided the night tourism program into three types: performance, participation, and landscape. Cao [21] expanded the classification to include performance, participation, landscape, and comprehensive type. From various studies, it is possible to see that night tourism activities can be categorized in the same way as typical tourism activities. It can include sightseeing, watching performances, and participating in tourism programs just like day-time tourism activities.

Night tourism received attention from major destinations with rich natural and cultural resources as enhancing competitiveness and advancing marketing strategies. Numerous cities, including Paris, Melbourne, London, Jerusalem, Baltimore, and Barcelona, promoted night tourism programs such as light festivals [22]. Night tourism, which has emerged as an alternative to securing tourism competitiveness, has been attracting more attention by the emergence of the night economy. Night tourism can lead to 24-hour economic development by generating 24-hour consumption by tourists [13]. Night tourism could trigger the development of the night economy of destinations. Evans [23] analyzed late-night events/festivals and confirmed that perceived benefits from night economy growth as improving the vitality of areas, expanding leisure venues, growing the number of citizens, increasing the number of jobs, increasing the number of tourists, and activating investments of other areas' businesses. Also, night tourism could enrich the local culture since it not only brings the tourist from outside but also gives a chance for consumption in the cities by local citizens [14,23].

However, over-tourism problems could also arise in night tourism, since it occurs during the night which is not considered to be normal tourism time. Night tourism could bring about conflicts between residents and tourists [14]. It causes inconveniences for resident such as noise at night [24], and this also lead to deterioration of tourism destinations due to residents' resistance [14]. In addition, it could also result in the decrease of the attractiveness of tourism destinations as Smith and her colleagues revealed that perception of crowdedness during night tours is significantly related to the decline of the attractiveness of the destination [15,24].

### *2.2. Over-Tourism*

UNWTO [1] defined over-tourism as "the impact of tourism on a destination, or parts thereof, that excessively influences perceived quality of life of citizens and/or quality of visitors experiences in a negative way." Goodwin [3] said over-tourism could describe destinations where hosts or tourists, locals or visitors feel that the number of visitors is too high and that the quality of life in the area or the quality of the experience has declined unacceptably. In short, over-tourism could be referred to as the negative impact of an intolerably large number of tourists. This concept emerged in the late 2010s, and studies on the effects and solutions of the causes have been conducted so far [2].

Over-tourism could cause serious problems at the destinations, bringing economic, social, physical, and environmental problems which impede sustainability of the destination. It can be understood from the perspective of sustainable tourism. UNWTO [25] explained sustainable tourism in three pillars: economic, social, and environmental sustainable development. Economic sustainable development means generating prosperity of society and cost effectiveness of all economic activity for maintaining economics in the long term. However, over-tourism could lead economic unsustainability by a "tragedy of the commons" [4]. Social sustainable development emphasizes local communities and maintaining and strengthening their lives and culture. Over-tourism could harm this aspect by causing deterioration of residents' quality of life [5]. It could lead to conflicts between locals and visitors [14] and if it becomes more serious, over-tourism can cause residents' resistance [14]. Environmental sustainable development means conserving and managing resources especially for biological diversity and natural heritage. It also emphasizes actual actions for minimizing pollution. However, over-tourism could have negative effects on the physical and environmental resources of the destination [5].

For solving the problems due to over-tourism, it is easy to find the various efforts that have been made thus far. Also, various studies have introduced ways of relieving the negative effects of over-tourism, including spatial dispersion of spots for tourists [2], temporal and spatial distribution of tourists [5], educating residents, [6] and a taxation strategy [7]. Understanding of the nature of tourism, which is a demand-driven industry, it should be recognized that it is very difficult to solve the deformation phenomenon in large numbers of tourists with education or regulation strategies. If the destination regulates the number of tourists compulsorily, they might face the burden of the quantitative reduction of tourists [8]. In contrast, temporal or spatial distribution will be a better solution since it could affect target tourists' behavior without any enforcement [2,5].
