The DashiweiTiankengin Guangxi Zhuang Autonomous Region. [Xinhua]

A group of Chinese and British scientists have entered the world's largest tiankengs, a group of giant sinkholes, to examine their air and water quality and look for new species.

Another team of scientists explored the Dashiwei tiankengs, nearby Leye City, Guangxi Zhuang Autonomous Region, in 2000 but were limited by technology and equipment. The tiankengs together form a pit 600 meters long, 420 meters wide and between 511 meters and 613 meters deep – or enough to fit two Eiffel towers stacked on top of each other.

Tiankeng literally means "heavenly pit" in Chinese. It is a unique geological feature that usually forms in clusters and are mostly found in Guangxi, as well as neighboring Chongqing Municipality.

The well-known Leve and Fengshang Tiankengs in Guangxi, which have an extensive cave system, was added to UNESCO's Global Geoparks Network at the beginning of this month.

(Xinhua News Agency October 18, 2010)