Karst - Stockfoto

Outside the Royal Arch cave system near Chillagoe, Queensland, Australia. This Royal Arch cave and other impressive caves have daily ranger-guided tours as part of the Chillagoe-Mungana Caves National Park. This limestone bluff shows distinctive karst topography, a landscape formed from the dissolution of soluble rocks such as this limestone. Karst is characterized by underground drainage systems with sinkholes, dolines, and caves. Cave tours are a popular tourist attraction in the Chillagoe district. The world's largest limestone karst is also in Australia, the extensive Nullarbor Plain.