Mendip Hills to the development of cave diving in Britain. The first cave dive was attempted at Swildon's Hole in 1934, and the first successful dive was achieved the following year at Wookey Hole Caves, which has the deepest sump in Britain at 76 m (250 ft). The cave complexes at St. Dunstan's Well Catchment, Lamb Leer, and Priddy Caves have been identified as Sites of Special Scientific Interest. The deepest cave in the Mendip Hills is Charterhouse Cave with a vertical range of . Many caves in the Mendip area were excavated for archaeological and natural history studies by pioneer explorer
Wookey Hole Caves the historic machinery. Visitors to the site are still able to watch a short video of the paper being made from cotton. Other attractions include the dinosaur valley, a small museum about the cave and cave diving, a theatre with circus shows, a house of mirrors and penny arcades. In 1956, Olive Hodgkinson, a cave guide whose husband's family owned the caves for over 500 years, was a contestant on "What's My Line?" The cave and mill were joined, after purchase, by Madame Tussauds in 1973 and operated together as a tourist attraction until there was a management team buyout