This shelter is a unique testimony to the living conditions of civilians during the war. Built to protect the 400 children of the only school in Bourg-la-Reine from shelling, the shelter, which follows a so-called "rack-and-pinion" route, complies with the passive defense recommendations issued before the war by the French government: a hallway broken by right angles to mitigate the effects of the bombs. A supporting exhibition presenting the history of the construction of this shelter and the local context precedes the free visit. For security reasons, groups of 10 people will be formed.