Veryovkina Cave is 2,212 meters (7,257 ft) deep and is the deepest known cave on Earth. Its entrance is situated 2,309 meters (7,575 ft) above sea level in Abkhazia, Georgia.

The entrance of the cave has a cross-section of 3 m × 4 m (9.8 ft × 13.1 ft), and is located in the Arabika Massif, Gagra Mountain Range of the West Caucasus, on the pass between the Krepost and Zont mountains, closer to the slopes of Mt. Krepost. The depth of the entrance shaft is 32 meters (105 ft).

More Info: en.wikipedia.org