Ancient forest found at bottom of huge sinkhole in China

There are trees up to 40 metres tall at the bottom of a giant sinkhole in China.

Scientists think it could hold undiscovered plant and animal species.

Cave explorers in the southern China region of the Guangxi region discovered a forest inside a sinkhole. This is the largest of the 30 sinkholes in Leye County.

A senior engineer at the Institute of Karst Geology of the China Geological Survey told the state news agency that the site had three caves in its walls and a primitive forest at the bottom.

Scientists trekked for hours to reach the base of the sinkhole. The dense undergrowth on the floor came up to his shoulders as well as the trees.

He said that he wouldn't be surprised to know that there are species that have never been reported or described.

The landscape is called a karst landscape because it is formed by the dissolution of bedrock.

This means that there are caves in the area. This one is rare as it is both deep and shaped so that the large trees can grow.