In the middle of the Cold War, one of the largest civil defence facilities in the world was built in the city of Lucerne: In the event of an emergency, 20,000 beds and hundreds of toilet facilities would have been set up on the roadways of today's car tunnels through the Sonnenberg. A third of the city's population would have found refuge here until the closure of the facility in 2006. At the same time, a seven-storey building was constructed in the mountain above the centre of the tunnel with a command post, emergency hospital, operating theatres, kitchen, laundry and much more. Among the topics discussed on the guided tour are the threat perception of the small state of Switzerland between East and West, the fear of a third world war and the atomic bomb, as well as the redimensioning and conversion since 2008.
One- to two-hour tours can be booked according to choice: on foot tours, impro theatre tours or Segway tours.