We have already written about a newly discovered giant sinkhole in China that has a primeval ‘lost world’ inside, but this one takes it to another dimension. Imagine a sinkhole so deep it takes half a day or more to hike from top to bottom and back. That’s the reality of Xiaozhai Tiankeng, also known as the Heavenly Pit, the world’s deepest sinkhole. Located in Fengjie County, China, this awe-inspiring geological marvel plunges a staggering 2,172 feet (662 meters) into the earth.

For centuries, the Xiaozhai Tiankeng remained hidden from the outside world. Locals may have known about it, but it wasn’t until a team of British explorers stumbled upon it in 1994 that it gained international recognition. Formed over millions of years by the relentless erosion of underground rivers dissolving limestone, the sinkhole boasts a nearly vertical drop that takes your breath away.

The Xiaozhai Tiankeng is more than just a giant hole in the ground. Its unique microclimate, with its own weather patterns and lush vegetation, has fostered a distinct ecosystem. A total of 1,285 plant species, among them the ginkgo, along with various rare animals such as the clouded leopard and the Chinese Giant Salamander, have been discovered in the sinkhole. Due to its remote location, many plant and animal species found within the sinkhole haven’t been documented elsewhere, potentially representing new discoveries for science.

Conquering this giant requires serious planning and physical fitness. The descent, which can take up to 4 hours, involves navigating steep, uneven terrain. The climb back up is no easier, and proper equipment and support are crucial. There’s a 2,800-step staircase to make the hike easier though.

The scale of the Xiaozhai Tiankeng is mind-boggling. The Empire State Building – this behemoth of a skyscraper could be swallowed whole by the sinkhole, with plenty of space to spare! An underground river still flows beneath the sinkhole, likely contributing to its ongoing formation. The unique environment within the sinkhole has its own weather system, with temperatures often cooler than the surrounding area.

What’s it like to be at the bottom of the world’s deepest sinkhole? For a glimpse into the wonders of Xiaozhai Tiankeng, check out this BBC Reel video that takes you inside it.