Since February 2013, groups of friends, colleagues, families and pupils have been voluntarily imprisoned in the underground of Bern to experience an adventure that is unique in Switzerland: Completely on their own, the group has to explore spaces, find hiding places and secret doors, and find the meaning behind mysterious objects, devices and signs in order to track down the escape route and finally regain freedom. Similar situations are known from films or computer games, but here the participants themselves are the main actors, and one is not dealing with virtual objects on a screen, but with real objects.
