New measurements and exploration in China's Shuanghe Cave have confirmed it as the longest in Asia, and sixth-longest in the world. At least for now, because over time, new branches and connections have come to light.
At 238 kilometres (about the distance from New York City to Providence, Rhode Island, it's almost a world in itself, described by researchers as "a karst museum with eight main caves and over 200 branches." Since 1988, Chinese and foreign researchers have been exploring, locating rare species and valuable fossils—and they're not done yet.
At 365 known miles, Mammoth Cave, in Kentucky, is still the champion for length; that's a bit more than twice the length of Shuanghe. For more beautiful images of Shuanghe, located in Guizhou Province, click HERE