Priddy Caves (grid reference ST540505) is an Area: 67.6 hectare (167.0 acre) geological Site of Special Scientific Interest at Priddy in the Mendip Hills, Somerset, notified in 1965. The entrance to St Cuthbert's Swallet is incorporated in the adjacent Priddy Pools SSSI. The Priddy Caves System contains about 16 km of surveyed cave passages divided between a number of major and minor networks. All the caves are sink hole systems, fed by sink holes at the ground surface. In all the caves, the detailed disposition and form of the passages can be seen clearly to have followed marked lines of natural weakness in the rocks.