The Li River originates in the Mao'er Mountains in Xing'an County and flows in the general southern direction through Guilin, Yangshuo and Pingle.

In Pingle, the Li merges with the Lipu and Gongcheng, becoming the Gui, and in turn falls into the Xijiang, the western tributary of the Pearl River.

Mean flow past Guilin is 215 cubic meters per second, and alluvium sediments consisting of well-sorted gravels covered by silty sand, forming floodplains and terraces along its route.

These towers consist of strong and massive limestone forming near vertical sides with base diameters less than 1.5 times their height.

Fenglin evolves from Fengcong by slow and continuous tectonic uplift, associated with the Himalayan orogenic zone, and even slower erosion of the towers.