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
West Cornwall Bryophytes Site of Special Scientific Interest West Cornwall Bryophytes Site of Special Scientific Interest The West Cornwall Bryophytes Site of Special Scientific Interest is a group of seven locations of former mining activity, that form a single SSSI and Important Plant Area in western Cornwall, England, United Kingdom. The site is noted for its biological characteristics and derives its name from the rare bryophyte species found there. The SSSI comprises seven individual sites, spread over a radius around the towns of Camborne, Redruth and Helston, totalling an area of . All of the areas making up the site are situated on disused mining land. The copper