This fortress, which is the largest in the Alps, was completed in 1838 but was never actually used for the purpose of war. It served as a munition storage place until it was taken over by South Tyrol to be used for cultural purposes. So far the lower and middle fortress have been rebuilt to house exhibitions. Cellar corridors were extended underground and connected by a vertical shaft to the uppermost, destroyed, powder magazine. A staircase was installed here, free standing like a sculpture, so that the view of the exterior was not impaired. A new building made of concrete extends the ruins which are covered with a steel roof. The rest of the additional buildings were built in patinated black steel, whose open galleries seems to sway over the surface of the reservoir.