karst

Landscape characterized by remarkable surface and underground forms, created as a result of the action of water on permeable limestone. The feature takes its name from the Karst (meaning dry) region on the Adriatic coast of Slovenia and Croatia, but the name is applied to landscapes throughout the world, the most dramatic of which is found near the city of Guilin in the Guangxi province of China. Karst landscapes are characterized by underground features such as caves, caverns, stalactites, and stalagmites. On the surface, clints, grikes, gorges, and swallow holes are common features.

Limestone is soluble in the weak acid of rainwater. Erosion takes place most swiftly along cracks and joints in the limestone and these open up into gullies called grikes. The rounded blocks left upstanding between them are called clints.