A highly dissolved land surface consisting of an intricate network of intersecting roofless dissolution-widened fissures, cavities, and tubes dissolved into the carbonate bedrock. Other features include vertical fractures, shafts, spikes, spires and eroded rills of carbonate rock.

(synonym: subcutaneous zone) The interval below the organic soil and above the main mass of largely unweathered soluble bedrock, consisting of highly corroded bedrock, residuum, and float. Thickness varies from absent to a maximum of 30 meters (100 feet). The epikarst is relevant to the storage and transport of water in the karst system, and to foundation stability.

The upper zone of a karst area that extends downward as sinkholes, fractures, fissures, and other surface karst features to where the natural porosity of the bedrock is located. Epikarst can range from almost nonexistant to tens of meters deep.