Sprawling Ancient Forest Discovered in Remote China Sinkhole

Researchers studying the "lost world" say it may be home to undiscovered species.

river view of Guangxi
Karst mountains in the Guangxi region of China, where the sinkhole was discovered.

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Like something straight out of the imagination of Jules Verne, a team of Chinese scientists has uncovered a potential “lost world” at the bottom of a massive sinkhole. 

The discovery, located within China’s remote Guangxi region, features a sinkhole measuring over a thousand feet in length, 492 feet wide, and with a depth of nearly 630 feet. After first rappelling 328 feet into the abyss, Chinese spelunkers and speleologists from the Institute of Karst Geology of the China Geological Survey found themselves trekking through a dense forest to reach the bottom. 

According to Xinhua News, the primeval landscape features ancient trees with heights in excess of 130 feet, as well as massive shade plants as tall as the explorers’ shoulders. The previously-undisturbed site is so inaccessible that researchers believe it may be home to unique species of plants and animals. 

"I wouldn't be surprised to know that there are species found in these caves that have never been reported or described by science until now," Chen Lixin, leader of the expedition team, told Xinhau

A Lush Region Dotted With 'Heavenly Pits' 

The discovery is the 30th such sinkhole that has been found in the mountainous Guangxi region, part of a 240,000-acre UNESCO World Heritage site known as the South China Karst. The karst topography is formed by the dissolution of soluble rocks such as limestone from rainwater, which leads to the formation of extensive cave system and sinkholes. 

According to Livescience, an estimated 25% of the U.S. and 20% of the world’s landmasses is made from karst or psuedokarst. In Mandarin, massive sinkholes like those found in Guangxi are known as "tiankeng," or "heavenly pits.”

"So in China you have this incredibly visually spectacular karst with enormous sinkholes and giant cave entrances and so forth,” George Veni, the executive director of the National Cave and Karst Research Institute (NCKRI) in the U.S., told LiveScience. “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." 

Squeezing into sinkholes isn’t generally a problem in China, where words like “enormous” do not do justice to the incredible wonders dotting its karst topography. As you might expect, it’s also home to the world’s largest sinkhole, the Xiaozhai Tiankeng, which spans 2,054 feet long, 1,762 feet wide, and burrows between 1,677–2,172 feet into the earth.

You can see a video of this mammoth sinkhole, which China has also turned into a tourist attraction, below.