"Cruising" is a concept which designates a practice of social interaction that consists of anonymous sexual encounters, mostly among homosexuals, in open and/or closed public spaces. Coastal dunes and beaches are examples of open public spaces where these sexual practices are widely carried out, to the extent that the so-called "Four S's" (Sand, Sun, Sea and Sex) have even been defined in the literature. Abundant studies have addressed the topic of relationships between tourism and sex, but few have analyzed the consequences of these practices on the natural environment, especially when the spaces where these activities take place are protected areas. In this work, the spatial distribution and the environmental impacts of cruising in a protected coastal dune system are characterized and assessed. There is no intention to criticize the actions of some of the LGBTI community. The sex spots (places for sexual encounters) were located and inventoried by fieldwork. The dimensions or internal distribution, as well as the sexual use, geographical position, vegetation cover and attributes, and environmental impacts or lack of management actions were examined and collated in a geographic information system (GIS). The results show that the distribution of the 298 identified sex spots, which occupy an area of 5763.85 m2, is related to the distance to authorized paths in the protected area, to the presence of bushy and dense vegetation, and to stabilized aeolian landforms or ones formed by vegetation (nebkhas). The bigger the sex spot, the higher the number of people who made use of it, the greater the likelihood of it being a low-lying area covered by vegetation, and the larger the amount of waste. The activities developed in these sex spots impact directly on the aeolian landforms and on eight native plant species, three of which are endemic species.