Historic city centres of European cities are one of the most important elements of the European cultural heritage. They are places that attract many visitors due to their relevance in terms of heritage, but the recent growth of tourist flows constitutes a threat to the conservation of their values. In some European cities, such as Venice or Barcelona, the debate has taken to the streets, and there is significant social mobilization taking place, with very belligerent positions against tourism (anti-tourism, tourismphobia). The mass media also generates discourse on the topic and places the debate on urban tourism sustainability at the forefront of the public debate. In this context, this article reviews the state of the art on tourism impact and identifies, describes and evaluates the different dimensions of tourist pressure based on a case study: the historic centre of the city of Donostia-San Sebastián (Basque Country, Spain). The main goal of the research is to help determine how tourist pressure affects the safeguarding of “historic urban landscapes” and the desirable or desired models of city and tourist destination.