This is the ancient underground route of a river, forming a system of caverns and tunnels, with a development of over 2 km, partly occupied by the waters of a small lake. Scientific research in 1897 brought to light the remains of two pile dwellings, Neolithic and later period objects. So yes, in the Neolithic period someone inhabited this cave, which was occupied by water at that time. It was also a shelter for many in the Neolithic, Bronze Age and Early Iron Age, Lucanian-Greek and Roman periods. Towards the middle of the 11th century, it became a place of worship. It is already impressive at the entrance, 20 metres high and 15 metres wide. After walking 50 metres, you board a raft and begin the actual visit. From the vault hang numerous stalactites that are reflected in the water. Approaching the first hall, with the roar of a waterfall in the background, the cave divides into three main branches. The Braccio della Sorgente, from which several tunnels branch off, is rich in concrete formations. The Braccio Centrale is somewhat unadorned, however. The Braccio Principale has several branches, low, narrow tunnels adorned with rich, elegant and fragile concrete formations.