[Photo provided to China Daily]

Most sinkholes are in places where few people tread. Ren Juangang, a senior engineer from SGII, who is in charge of the Hanzhong sinkholes survey, led people to Didonghe Sinkhole, a large sinkhole with a diameter of 380 meters.

A defining characteristic of Didonghe is its Shangri-La-like charm. It is flanked on all sides by green plants with a few streams flowing slowly down the sides to the emerald pool in the center. On the mild inclines near the lake, there are fields of stones the size of a chestnut. And there is a giant karst cave, on the roof of which are hundreds of stalactites.

Li Yichao said that he was "amazed at the various shapes of the stalactites".

Each of the sinkholes has its own characteristics and they are rich natural and biological resources for scientific research.

In Luojiaba town, where several other sinkholes are located, they have found hanging coffin tombs, an ancient form of burial.