Gaping Gill (also known as Gaping Ghyll) is a natural cave in North Yorkshire, England. It is one of the unmistakable landmarks on the southern slopes of Ingleborough – a 105 metres (344 ft) deep pothole with the stream Fell Beck flowing into it. After falling through one of the largest known underground chambers in Britain, the water disappears into the bouldery floor and eventually resurges adjacent to Ingleborough Cave.
The first recorded attempted descent was by John Birkbeck in 1842 who reached a ledge approximately 55 metres (180 ft) down the shaft which bears his name. The first complete descent was achieved by Édouard-Alfred Martel in 1895.
Due to the number of entrances which connect into the cave, many different routes through and around the system are possible. Other entrances include Disappointment Pot, Stream Passage Pot, Bar Pot, Hensler's Pot, Corky's Pot and Flood Entrance Pot. In 1983 members of the Cave Diving Group made the underwater connection into Ingleborough Cave.