A karst is a type of landscape formed from the dissolution of soluble rocks, such as limestone, gypsum, or salt. This process creates unique geological features, including sinkholes, caves, and underground rivers. Karst regions are often characterized by rugged terrain and a lack of surface water, as much of it drains underground. Karst formations are found in many parts of the world, including famous areas like the Guilin region in China and the Carlsbad Caverns in New Mexico. These landscapes are important for biodiversity and can also serve as significant water sources, as they often contain aquifers that store groundwater.