C344 A Mysterious Cave

It's a karst cave.

A karst cave referred to a hole formed by the erosion of limestone by rain or underground water. It was also known as the stalactite cave, the limestone cave.

The place with the most karst caves in China was located at the southwest border. It was also known as the world's best mountain and river cave.

The formation of the karst cave was about 100,000 years ago. Currently