Gaping Gill is a natural cave in North Yorkshire, England. It is one of the unmistakable landmarks on the southern slopes of Ingleborough – a 98-metre (322 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.

Rat Hole is one of the entrances to the Gaping Gill cave system, located in the north bank of Fell Beck 30 metres (33 yd) upstream of Gaping Gill Main Shaft. A small, awkward, tube-like passage descends into a stream passage, and hence to a 100-metre (330 ft) shaft into Gaping Gill Main Chamber. The sharp and loose nature of the rock, and the quantity of water prevented full exploration for over 80 years, but the current route is described in one guide book as "a technical and exhilarating adventure". It lies within the designated Ingleborough Site of Special Scientific Interest.