A famous limestone abyss high on the southern slopes of the Corno d'Aquilio, west of the plateau's centre. The entrance is a modest oval shaft in the pasture; from it the cave drops in a series of pitches to a known depth of 985 metres, making it one of the deepest in Italy. For most of the twentieth century it was thought to be the deepest in the world, and Italian speleology cut its teeth on the long ropework descents needed to reach the bottom.
Casual visitors can walk to the gated entrance from the rifugio at Malga Preta in around half an hour — there is an information panel and dramatic views over the Adige valley below. The cave itself is only open to qualified cavers; even seeing a team rig the first pitches is impressive on a clear summer day.