Is the most important active cave of  Supramonte of Urzulei.

This cave represent one of the largest karst caves of the Supramonte of Urzulei.

The cave de S’Edera named after a large ivy plant near the entrance, is located in the locality of Fennau in the southern side of the Supramonte of Urzulei. This natural cavity is part of a very large karst system of which are known only few portions.

Its development is about 16 kilometers, the negative slope of -256 m and its entrance is located at an altitude of 944 m above sea level. The cave is divided into different levels with galleries and very large rooms adorned with beautiful concretions. Waterfalls and enchanting kettles adorn the descent. Inside they flow three rivers that gather to form a unique underground stream that emerges in the famous source of Su Gologone, located 22 km to the north, on the northern side of the Supramonte. Its exploration began in the early sixties and is continued until a few years ago and has been for an entire generation of cavers, sardinian and beyond, a difficult cave, one of the deepest of the island where the explorations did not lead easy results.