||In the last decades, the world population has increased its physical sports activities in the natural environment. According to the last Eurobarometer survey about outdoor sports, Spain figures in third place with 53% of the population claiming that have been involved in physical outdoor activities, after Finland (67%) and Austria (54%) (European Commission, 2018). As a result, there has been an increase in overcrowding in Protected Areas, which has attracted the attention in the Spanish mass media revealing the consequences that have already demonstrated in various environmental (Cole, 2008; Newsome, 2014; Pickering, 2010; Salesa & Cerda, 2020), social (Weiler et al., 2019) and security studies (Moscoso, 2004). On that point, different public and private entities requested solutions to manage overcrowding in different natural parks through the determination of the Tourist Carrying Capacity (TCC), i.e. maximum number of people who can visit an area at the same time, without damaging the physical, economic or sociocultural environment, nor cause an unacceptable decrease in the quality of visitors satisfaction (OMT, s. f.). This article aims to show the application of the Cifuentes (1992) methodology about the TCC in 17 trails of Alt Pirineu Natural Park (PNAP), within Vall Ferrera to be included in the next trail guide of the park.