Krubera-Voronja Cave
Also known as the Cave of Kruber, Voronja is the deepest cave in the world with recent measurements extending to a total depth of 7188 feet (2191 m). It was the first cave to be explored to a depth of more than 2 km down.
On August 5th 2007, an international expedition with 56 members went in and the interesting thing is, they said that the cave system could be deeper. "The caving game is far from over. It won't be; not as long as deeper abysses call out to be explored" said Alexander Klimchouk, a renowned speleologist.
The Crows' Cave (that what it means) is located in Georgia in the Arabika Massif of the Gagra Range, near the coast of the Black Sea.
Known as "the Sistine Chapel of crystals," Mexico's Cueva de los Cristales (Cave of Crystals) contains some of the world's largest known natural crystals—translucent beams of gypsum as long as 36 feet (11 meters). The cave is 950 feet (290 meters) underground
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