Saint Petersburg is one of the most visited cities in the world. Beyond the beautiful evocative facades downtown, an unique world, unknown to most visitors, hides itself: the world of Kommunalki. Still nowadays, almost one hundred years from the October Revolution, a lot of people of different ages and from different places and social background, live together in rooms inside big apartments where they share communal areas such as a kitchen, a bathroom and a corridor. The inhabitants of such places have personally experienced the consequences of applying an utopian concept to daily living. The analysis of that will be the starting point, as well as a common thread, for a reflection on the modern meaning of community and human relations as well as on both the social and the economic transformations affecting the cities.