In the area of Frasassi Caves, near Mount Valmontagnana, passing through a dangerous and narrow corridor called "Fiorini", you enter the Buco Cattivo (Ugly Cave).  It was discovered in 1949; it wals told by a farmer that steam came out from the pit, like the "mouth of hell". To reach this place from San Vittore Terme continue towards the village of  Palombara di Ferro. Going into the bush, follow a track debris which soon leads to a gully to be climbed. The climb is quite hard and, once completed, there's a sequence of slides. Finally, it opens the low entrance to the Ugly Cave Hole. The Ugly Cave (also known as the "Rate Cave") opens at an altitude of 78 m, heading north, and to find it you must cross the thick bush again.