For the city and its actors, ruins are often considered as problems to manage. However, they are today experiencing an incredible upsurge in popularity (High, 2013; Sumida, 2015). Considering this growing popularity, the presence of ruins could become a strong engine of tourism. Although quite marginal, this tourism gives us an insight on how we perceive ruins today. The Urban Explorer is an inevitable figure of this specific form of dark tourism. To better understand its practice and its perception of ruins, we therefore propose to detail what is urban exploration, while analyzing the explorers » main motivations.