The Burren is an area of Co Clare known for its karst landscape. It measures approximately 250 square kilometres and is enclosed roughtly within the circle made by the villages of Ballyvaughan, Kinvara, Tubber, Corofin, Kilfenora and Lisdoonvarna. The Burren National Park is one of six National Parks in Ireland and the smallest in size (15 km2).The Burren National Park Visitor Centre is located on Church Street in Corofin. The Burren is rich with historical and archaeological sites. There are more than 90 megalithic tombs in the area, portal dolmens (including Poulnabrone dolmen), a Celtic high cross in the village of Kilfenora, and a number of ring forts - among them the triple ring fort Cahercommaun on the edge of an inland cliff, and the exceptionally well-preserved Caherconnell Stone Fort. Corcomroe Abbey is one of the area's main scenic attractions. The Burren is renowned for its remarkable assemblage of plants and animals. The region supports many rare Irish species, some of which are only found in this area. The area is known for its limestone pavements and is a popular destination for rock climbers.