Krubera Cave
The difference in elevation of the cave's entrance and its deepest explored point is . It became the deepest-known cave in the world in 2001 when the expedition of the Ukrainian Speleological Association reached a depth of which exceeded the depth of the previous deepest-known cave, Lamprechtsofen, in the Austrian Alps, by . In 2004, for the first time in the history of speleology, the Ukrainian Speleological Association expedition reached a depth greater than , and explored the cave to . Ukrainian diver Gennadiy Samokhin extended the cave by diving in the terminal sump to 46 metres' depth in 2007 and then to 52 m in 2012, setting successive world records of 2,191 m and 2,197 m, respectively. Krubera is one of the two known caves on Earth deeper than 2,000 metres.
Deer Cave
Deer Cave was known as the largest cave passage in the world until the discovery of Sơn Đoòng cave in Phong Nha-Kẻ Bàng National Park in Vietnam. It is part of the Gunung Mulu National Park, a UNESCO World Heritage Site characterised by amazing caves and karst formations in a mountainous equatorial rainforest setting. 
The Clearwater cave, with approximately of known passages, is considered the longest cave system in Southeast Asia. It is recognised for its clear underground stream, popular with tourists. The Wind cave is located on the same trail leading to Clearwater cave, and is known for its blowing wind. It contains a chamber dubbed King’s Room, a cavern containing huge columns of stone on both the ceiling and the floor. The Lang cave is the smallest of the caves open to the public. However, its size allows up-close opportunities to see some of the common cave inhabitants such as bats and swiftlets.