1. Introduction

The term ‘overtourism’  appeared in the last few years in media reports on the negative effect of mass tourism on host communities and/or the natural environment.

The notion of overtourism was popularised thanks to the internet travel website Skift (2018). An official definition of overpopulation also appeared, which reads “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” (UNWTO 2018).

It must be added that the phenomenon is nothing new as the issue has been the subject of discussion in academic circles for many years (Dredge 2017). As early as the 1970’s, special indicators were developed to define the optimal size of tourist traffic for various regions. The literature mentions three basic measurements: absorption indicator, capacity indicator and flow indicator (Kostrowicki 1970, O’Reilly 1986, Canestrelli  et al. 1991). Meanwhile, R.W. Butler (1980) published a theory on the evolution cycle of tourist areas, and Doxey (1976) constructed an irritation index illustrating the change in residents’ attitudes to tourists.

A tourist area has its limitations resulting from the usable area available and its reaction to tourist traffic (Szromek 2012). A key problem is defining the permissible size of traffic, above which it may be considered excessive. For cities that are large centres of tourism and are faced with an invasion of tourists, proposed indicators define the optimal level of socio-psychological capacity (Russo 2002).

            Later research confirmed that the behaviour of visitors, the length of their stay, the volume of tourists and the type of tourism are in fact equally as important as the number of tourists (Lindberg et. al.,  1997). While the influence of tourism on the physical environment is relatively easy to define, it is decidedly more difficult to assess the social effects of an influx of tourists. A concept based on the host community’s tolerance towards tourists is not only subjective, but is also difficult to measure. The level of tolerance among residents towards an influx of tourists varies depending on local and private interests (McCool et. al 2000; Saveriades  2000).

There are also alternative research concepts such as the Limits of Acceptable Change -  LAC, which allows for assessment of the degree to which the effect of tourism can be accepted by local parties interested in its development (Lucas et. al. 1985, Frauman, et. al 2011). In periods of increased financial need, residents may have a more tolerant attitude and endure the negative effects of tourism due to the potential economic benefits. Discussion on the LAC concept and other similar approaches has meant that instead of using figures to illustrate the mass scale of tourist traffic, emphasis has been placed on qualitative analysis balancing the benefits and drawbacks of the development of tourism (Nijs 2017). Various approaches to tourism management have also appeared that go beyond limits on the number of visitors. The first, supported by the UNWTO, focuses on increasing tourist capacity in reception areas. Capacity can be increased through, amongst others, the use of intelligent hi-tech solutions (UNWTO 2018) or by increasing acceptance in the local community and stimulating entrepreneurship (Fang at al. 2016, Pearce 2018). Other approaches focus on the need to diversify forms of tourism and the building of proper relations between the interested parties involved in tourism. Attention should be drawn to the fact that the benefits and drawbacks are often not evenly distributed among the interested parties (Bianchi  2009, Koens et al. 2018).

2. Use function

The first use of the term overtourism dates back to the beginning of the 21^st century, when it was used to describe the danger of excessive exploitation of natural resources (Nelson 2002). Later, the term ‘turismofobia’ appeared in the Spanish media to describe the reaction of Barcelona residents to the excessive growth of tourism (Milano 2017, Martin et al. 2018). The notion of tourist saturation was also used to describe excessive saturation of destinations due to tourism (Milano 2017).

In a very short time, the term overtourism has come to be used to describe the negative effect of tourism, and has been applied to the problem of excessive numbers of tourists in many cities. The discussion around overtourism has brought attention to the negative consequences of the unchecked increase in tourism. It also pointed to possible limitations and voluntary compromises aimed at effectively preventing the growth of such problems (Russo et al. 2017, Stors et al. 2017).

A variety of regulations and formal restrictions on the reception of tourists can be put in place by local authorities or even by the governments of host countries (Jamal et al. 2014). Reports are appearing in the media of attempts to limit tourist traffic by limiting tourist numbers. In 2018 in Venice entrance fees to the city were introduced. The phenomenon of overtourism was studied in many European cities, such as Madrid, Palma de Mallorca (Garcia-Ayllon 2018), its effects were described in relation to Krakow (Kruczek 2019, Zmyslony et. Al. 2019) and Ljubljana (Kuscer 2019). Excessive number of tourists is observed in many port cities thanks to cruise tourism (Sans-Blaz 2019). Research in 13 European cities such as Amsterdam, Berlin, Copenhagen, Lisbon, Tallinn suggests however the abuse of the term ‘overtourism’ (Overtourism Overused) and verify 7 myths attributed to thins phenomenon (Koens 2018).

Overtourism applies not only to cities, but also to areas valuable in terms of nature, especially national parks, reserves, mountain and polar regions. The authorities in the Philippines have decided to close the paradise island of Boracay for six months to clean the beaches and allow the natural environment to regenerate. Similar action was taken by Thailand with regard to the famous Maya Bay beach on Phi Phi Leh island. Overtourism takes place in national parks, eg. in the USA and Europe (Balmford et al 2015, Kruczek et al. 2019).