Krubera Cave, also known as Voronya Cave (Russian for “Crow’s Cave”) is the deepest known cave on Earth. It is located in the Arabika Massif, one of the largest high-mountain limestone karst massifs in the Western Caucasus region of Georgia.
1. Mammoth Cave National Park
Mammoth Cave National Park is a U.S. National Park in central Kentucky, encompassing portions of Mammoth Cave, the longest cave system known in the world.