The S.M.I. (Italian Metallurgical Society) was a company of fundamental importance during the last two wars, as it mainly produced munitions. And for the same reason it was a target for any enemy. In order to protect its workforce (about 7000 workers at the peak of production), in 1930 the company proceeded with the construction of the largest private anti-aircraft shelter in the world, a system of tunnels for a total of about 1680 metres built at a depth of 20 metres, excavated in the rock and protected at every point by one metre of reinforced concrete. The particular ogive entrances guaranteed an indestructible access from the surface, and various technical devices allowed the evacuation of all the workers and their families from the factory-village in a very short time. The tunnels, actually used from 1940 to 1944, were equipped with infirmaries, air and water treatment rooms, a chapel and, in the last year of the war, even schoolrooms. The inscriptions on the walls are remarkable: "Did you know that a person walking around consumes 2 to 5 times more air than a person sitting quietly?", "In case of unforeseen situations, discipline is the best guarantee of safety" or "Be calm. You already have shelter in these stairs." A visit to the galleries also includes the museum about S.M.I., a company that was in operation until 2005. In addition to its history, the exhibition illustrates the research and innovation behind the company’s production and management, such as the ultra-modern workplace safety rules (from 1912), as well as the plans behind the entire (futuristic for the time) industrial village, and the construction of the shelters themselves.
