The Frasassi Caves are underground karstic caves located within Gola della Rossa e di Frasassi Regional Natural Park in the municipality of Genga, in the province of Ancona. The Frasassi Caves were discovered on 25 September 1971 by the CAI speleological group of Ancona. Inside the karstic cavities, visitors can marvel at the natural sculptures formed over 190 million years through limestone stratifications, thanks to the work of water and rock. Flowing over the limestone, the water dissolves small amounts of the limestone that then fall to the ground. This dripping continues over millennia, depositing and forming concretions of considerable size and sometimes quite interesting shapes. These are divided into stalagmites and stalactites. Their shapes and sizes of these virtual works of art have stimulated the imagination of speleologists, who have 'baptised' their discoveries by naming them in curious ways; some of the most famous stalactites and stalagmites include: the 'Giants', the 'Camel' and the 'Dromedary', the 'Bear', the 'Small Madonna', the 'Sword of Damocles' (a stalactite 7.40 metre tall and 150 cm in diameter), 'Niagara Falls', the 'Slice of Bacon' and the 'Slice of Lard', the 'Obelisk' (15 metre tall stalagmite in the centre of Hall 200), the 'Organ Pipes' (conical-lamellar concretions that resonate when struck), and the 'Witches' Castle'. The caves also hold ponds in which the dripping water stagnates and 'wells', which are cylindrical cavities up to 25 metres deep that can collect water or channel it to lower karstic levels. The visit to the cave lasts 70 minutes. Groups are accompanied by professional guides provided by the Frasassi Consortium. The path is 1.5 kilometres long, or about a mile. It is well equipped and easily accessible. The internal temperature is a constant 14 °C.