THE DEEPEST KNOWN CAVE ON EARTH

Krubera Cave, the world's deepest cave. This natural wonder "plunges 7,188 feet (2,191 m)
into the depths of the Arabika Massif, a limestone formation dating back to the Age of Dinosaurs."

It is located in the Arabika Massif of the Gagrinsky Range of the Western Caucasus, in the Gagra district of Abkhazia, Georgia. It became the deepest-known cave in the world in 2001 when the expedition of the Ukrainian Speleological Association reached a depth of 7,185 feet which well exceeded the depth of the previously deepest cave, Lamprechtsofen, in the Austrian Alps, by 80 m.