Tags: Cave.
Shuang River Cave Group (双河洞) is the longest cave in China the second longest in Asia and 20th longest in the world.It is located near the town of Wenquan in Suiyang County Guizhou Province.This gypsum and dolomite cave has carbon dioxide levels of approximately 400ppm with a constant temperature of about 13 degrees Celsius year round.The cave contains numerous waterfalls and at least three underground rivers some of which contain cave shrimp and fish weighing several pounds.