Photo: Song Wen/Xinhua/Getty

Cave explorers in the Guangxi region of China have found a secret ancient forest hidden inside a 630-foot-deep sinkhole.
Inside, explorers found a primeval forest with ancient trees measuring 130 feet in height, Chinese outletXinhua Newsreported.
The outlet added that it took the expedition team several hours to reach the bottom of the sinkhole, after they rappelled down almost 330 feet.
Team leader Chen Lixin told Xinhua that the plants they found at the bottom grew densely together, coming up to his shoulders.
The explorers referred to the sinkhole as “tiankeng” in Mandarin, or “heavenly pit,“AccuWeatherreported.
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“Because of local differences in geology, climate, and other factors, the way karst appears at the surface can be dramatically different,” he added.
“So in China, you have this incredibly visually spectacular karst with enormous sinkholes and giant cave entrances and so forth. In other parts of the world, you walk out on the karst, and you really don’t notice anything. Sinkholes might be quite subdued, only a meter or two in diameter. Cave entrances might be very small, so you have to squeeze your way into them.”
The Twitter video specified that the recent find brings China’s number of this type of sinkholes to 30.
It also mentioned that the newest sinkhole originated from an underground river system called Fugui, while the previous 29 came about from the Bailang underground river.
The country is also home to theworld’s largest sinkhole, known as the Xiaozhai Tiankeng in Chongqing’s Tiankeng Difeng National Park.
source: people.com