Cheddar Gorge a tourist destination. In a 2005 poll of "Radio Times" readers, following its appearance on the 2005 television programme "Seven Natural Wonders", Cheddar Gorge was named as the second greatest natural wonder in Britain, surpassed only by Dan yr Ogof caves. The gorge attracts about 500,000 visitors per year. Cheddar is a gorge lying on the southern edge of the Mendip Hills. The maximum depth of the gorge is , with a near-vertical cliff-face to the south, and steep grassy slopes to the north. The B3135 road runs along the bottom of the gorge. The area is underlain by Black
Wookey Hole Caves system that is formed within the Dolomitic Conglomerate is characterised by shallow loops linking low bedding chambers, or tall narrow passages, known as 'rifts', developed by phreatic solutional enlargement of fractured rifts. The streamway in the inner part of the system formed within the limestone is characterised by deep phreatic loops reaching depths as much as , with the water flowing down-dip along bedding planes and rising up enlarged joints. In the far reaches of the cave the passages descend to below sea level. Witcombe suggests that the name "Wookey" is derived from the Celtic (Welsh) for 'cave', ""Ogo"" or