This is a story about Roskilde Festival, the largest temporary city in Denmark. The book presents the concept of the festival and its basic values. Based on observations and analyses, the city plan, city spaces and architecture are presented including the interaction of the urban scenography with city life. The analyses are supplemented by 12 narratives, in which the participants tell us about their everyday life, the parties, the festival culture and their experiences with music, architecture and art. They present their territories and their places of meaning. In the theoretical and concluding parts, the focal points of the book are the potential of the temporary experience city to experiment with an open minded and socially inclusive urban life carried by carnival laughter, performative architecture and grotesque realism. The book points to a number of opportunities for a further development, and processing of the temporary city, which may also serve as a source of inspiration for those who are working with urban design, experience design and performative architecture. This is the second book from Aalborg University's research project "Experience City -- hybrid cultural projects and performative urban spaces". The 2009 publication EXPERIENCE CITY.DK focused on how hybrid cultural projects can provide leverage for a dynamic urban development and how they may affect the social life in the city.