Karst is a German name for an unusual and distinct limestone terrain in Slovenia, called Kras. The karst region in Slovenia, located just north of the Adriatic Sea, is an area of barren, white, fretted rock. The main feature of a karst region is the absence of surface water flow. Rainfall and surface waters (streams, for example) disappear into a drainage system produced in karst areas. Another feature is the lack of topsoil or vegetation. In geology, the term karst topography is used to describe areas similar to that found in Kras. The most remarkable feature of karst regions is the formation of caves.

Karst landscapes develop where the bedrock is comprised of an extremely soluble calcium carbonate rock such as limestone, gypsum, or dolomite; limestone is the most soluble calcium carbonate rock. Consequently, most karst regions develop in areas where the bedrock is limestone. Karst...