Reservoir Hole high and long. Prior to the discovery, the largest void under the Mendip Hills was thought to be "Main Chamber" in GB Cave, which is high. Before the find in 2012, the cave was already noted for a number of fine formations, and the newly discovered chamber, which has been named “The Frozen Deep”, contains pure-white pillars tall, as well as many stalagmites and stalactites. The possibility of a connection between Reservoir Hole and Gough's Cave, one of the show caves in Cheddar Gorge, has been raised, as the two caves are in close proximity. The stream in Reservoir Hole
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