Xiaozhai Tiankeng, Sinkhole in China
Xiaozhai Tiankeng, also known as the Heavenly Pit, is the world's deepest sinkhole.
It was discovered by specialists in 1994 during a survey for a planned power station.
The sinkhole has become a popular tourist attraction, with visitors descending the 2,800 steps to reach the bottom.
The area is not easily accessible and requires a certain level of physical fitness to explore.
Its unique ecosystem hosts a variety of rare and endangered species.
Source: Wikimedia