Caves of the Mendip Hills caves are listed below Caves of the Mendip Hills The caves of the Mendip Hills are formed by the particular geology of the Mendip Hills: large areas of limestone worn away by water makes it a national centre for caving. The hills conceal the largest underground river system in Britain. The hills consist of anticlines of Carboniferous Limestone lying over Devonian Old Red Sandstone, with the sandstone exposed on the summits. When a surface stream running off the sandstone reaches the limestone it sinks below ground through a "swallet", (also known locally as a "slocker"), continuing on its way down
Wookey Hole Caves gate servicing the paper mill was built about 1852. The tunnel excavated from the third chamber to the ninth chamber and then out to daylight was dug in 1974–1975 by ex-coal miners from the Radstock area. The show cave was further extended in 2015 by excavating a tunnel from the ninth chamber to the 20th chamber. The constant temperature of in the caves is used by Ford Farm of Dorset to mature Cheddar cheese in the 'Cheese Tunnel' – an excavated side tunnel between the ninth chamber and the exit to the show cave. Archaeological investigations were undertaken from 1859