Caves of the Mendip Hills then rising up a fracture in the rock. Few caves on the Mendip Hills are more than deep or a few kilometres in length, (with some notable exceptions, such as Swildon's Hole which is over long), but a number are complex with several levels of passages which have been abandoned by the water, for example those around Cheddar. The catchment area of the Cheddar Yeo, which rises in Gough's Cave, measures . Dye marking shows that some of the water travels underground for up to , taking up to 14 days to reach Cheddar. When Banwell Bone Cave was discovered
Caves of Meghalaya partially explored, for a total length of caves explored. With an explored length of , Krem Liat Prah in Jaintia Hills is the longest cave in Meghalaya, as well as India, and is listed among the longest caves in the world. Krem Liat Prah contains a huge passage called the "Aircraft Hangar." Since the MAA was established in 1994, the explored caves account for only about 5% of the total underground passages in the state of Meghalaya. Limestone mining for the cement industry is a major threat to the Caves of Meghalaya, causing a major collapse of the Krem Mawmluh