Caves of the Mendip Hills traverse from one cave to another through the underground rivers led to the development of cave diving; the first cave dive attempt in Britain took place at Swildon's Hole in 1934. The first successful cave dive in Britain was achieved the following year at Wookey Hole Caves, where the last sump is currently the deepest in Britain at . The cave complexes at St. Dunstan's Well Catchment, Thrupe Lane Swallet, Lamb Leer and Priddy Caves have been identified as geological Site of Special Scientific Interest. There are also caves within the Cheddar Complex SSSI. A selection of the better known
Prawle Point and Start Point Site of Special Scientific Interest Prawle Point and Start Point Site of Special Scientific Interest The Prawle Point and Start Point Site of Special Scientific Interest ( to ) is a 341.2 hectare biological and geological Site of Special Scientific Interest in southern Devon, notified in 1976. It includes the coastal headlands of Prawle Point and Start Point. The soft cliffs between Prawle Point and Start Point are recognised as being one of the most important sites for solitary bees and wasps in the UK. Over 100 species have been recorded including many rare and scarce species. This section of coast features an almost continuous