Krubera Cave

The Krubera Cave (or the Voronya Cave, sometimes spelled Voronja Cave) is the deepest known cave on Earth. It is located in the Arabika Massif of the Gagrinsky Range of the Western Caucasus, in the Gagra district of Abkhazia, Georgia

The difference in the altitude of the cave's entrance and its deepest explored point is 2,191 ± 20 metres (7,188 ± 66 ft). It became the deepest-known cave in the world in 2001 when the expedition of the Ukrainian Speleological Association reached a depth of 1,710 m (5,610 ft) which exceeded the depth of the previously deepest cave, Lamprechtsofen, in the Austrian Alps, by 80 m. In 2004, for the first time in the history of speleology, the Ukrainian Speleological Association expedition reached a depth greater than 2,000 m, and explored the cave to −2,080 m (−6,824 ft). The current maximum depth of 2,191 m was reached during a 46 m dive by Gennadiiy Samokhin into the terminal sump during the expedition of the Ukrainian Speleological Association in August–September 2007. The cave remains the only known cave on Earth deeper than 2,000 metres.