Swildon's Hole through route discovered on the Mendip Hills. Following a number of months of digging and blasting, the link was made in 1996 at the top of the Cowsh Avens Series, a climb above Sump 4. The water in the cave resurges in Wookey Hole Caves. This was first demonstrated (by pouring dye into the water) by Graham Balcombe and Jack Sheppard of the Cave Diving Group, who first passed Sumps 1 and 2 in the 1930s. Swildon's Hole Swildon's Hole is an extensive cave in Priddy, Somerset. At in length, it is the longest cave on the Mendip Hills. It
Mendip Hills been known about since the establishment of the Mendip lead mining industry in Roman times. However, many have been discovered or explored only in the 20th century. Specialist equipment and knowledge is required to visit the vast majority of the caves, but Cheddar Gorge and Wookey Hole Caves are two show caves which are easily accessible to the public. The active Mendip Caving Group and other local caving organisations organise trips and continue to discover new caverns. The Hills conceal the largest underground river system in Britain; attempts to move from one cave to another through the underground rivers led