In 1888, local resident Joseph Rapa discovered an underground natural cave to the rear of an ordinary house in the village of Xagħra, hosting abundant natural stalactite and stalagmite formations. Nowadays the cave is illuminated by electric lights as it is possible for the public to visit and be given a tour by the family guide. The entrance to the cave is via a 4m descent down a flight of steps leading into a large chamber. The calcification of water dripping from the cave ceiling has formed a number of striking columns. There are even a few helictites (curved stalactites). Most of the formations are now dry and the same colour as the surrounding rock but some remain semi-transparent and it is possible to see the rings formed as they grew.