Karst is largely restricted to the most soluble rocks, which are salt, gypsum and anhydrite, and limestone and dolostone. They are produced by aqueous dissolution, either acting alone or in conjunction with (and as the trigger for) other erosion processes.

The essence of the karst dynamic system is that meteoric water (rain or snow) is routed underground, because the rocks are soluble, rather than flowing off in surface river channels. It follows that dissolutional caves develop in fracture systems, resurging as springs at the margins of the soluble rocks or in the lowest places. A consequence is that most karst topography is "swallowing topography," assemblages of landforms created to deliver meteoric water down to the caves.

Forest Stone (or Shilin), one of famous Karst landscapes in South China, is in Lunan Yi Nationality Autonomous County, which is about 120km from Kunming and requires only a three-hour drive. It was inscribed on UNESCO's World Heritage List with Libo County in Guizhou Province, and Wulong County in Chongqing City. It covers an area of 400 square kilometers (96,000 acres) and includes both large and small stone forests, as well as many other scenic spots.

"The rocks of the Stone Forest are as high as scores of meters that one can only enter by climbing. The stones piercing towards the sky are just like thousands of horses. The cliffs and caves in it are all blue. There are underground rivers whose water is as cool as snow. It's said that someone saw two plum trees on the rock in winter. The two trees bore much red fruit on them. But he couldn't pick the fruit when he approached. The next day he came to look for the trees but the trees could never be seen again. So the place is called Liziqing Plum Tree Valley (A Record of Lunan Prefecture, the 57th year of the reign of Emperor Kangxi of the Qing Dynasty).

Liziqing above-mentioned is the Stone Forest Scenic Area now and also called "Daxiaoshilin" (the Big and Small Stone Forest). That is one of the earliest descriptions in history books. Covering an area of 12 square kilometers, the Stone Forest Scenic Area includes five sub areas, i.e. Bushaoshan in the northwest, Dashilin and Xiaoshilin in the middle, Wannianlinzhi in the south and Liziyuanqing in the east. Being deep, remote, dangerous and strange are its main features.