The outcrop of Permian strata to the east of Leeds exhibits a variety of karstic and palaeokarstic features. The area is crossed by an extensive network of dry valley systems and lacks surface water. Two different karst types are recognized: dolomite and dolomitic limestone karst, and gypsum karst. Dolomite and dolomitic limestone karst is characterized by small isolated dolines whereas gypsum karst is characterized by large-scale dolines, many occurring in groups. An appreciation of the karstic nature of parts of the Permian outcrop is becoming increasingly important because of pressure from development and waste disposal.