Resumo: Despite its economic benefits, the large increase in urban tourism has led to various negative consequences, especially in urban areas with a high tourist concentration, manifested in phenomena such as touristification and tourism phobia. This article presents the application and testing of a method to detect tourism overcrowding in cities through cluster calculations, using the Arcgis tool. It is based on a multicriteria evaluation of the tourism supply and the extraction of information from photographs on the Flickr platform through big data. Its objective is to establish a hierarchy of tourism pressure. Subsequently, demographic changes are examined to identify displacements and problems in neighbourhoods most affected by tourism concentration. The methodology is applied to Spanish cities renowned for urban tourism such as Barcelona, Bilbao, Madrid, and Valencia. The obtained results are considered optimal, as they detect previously identified neighbourhoods and discover others with a lower accumulation but with indications of tourism concentration. It is evident that upon reaching certain levels of tourism concentration, demographic consequences are generated, such as the displacement of vulnerable people, which is common to the four case studies. This valid and replicable method can be extended to other types of tourism and is suitable for making comparisons and measurements in similar spaces. For smaller scales or detailed studies, the expansion of the method and the integration of additional tools could be considered.
