Cheddar Complex the Pleistocene period. Cheddar Caves contain both active and fossil systems. The active cave system is one of the most heavily studied karst systems in Britain with reference to the conduit and diffuse flow characteristics of its hydrology. Charterhouse Caves include four major swallet caves that provide an indisputable record of Pleistocene landform development in the Mendips and surrounding area. Sun Hole Cave provides a varied fauna radiocarbon-dated to the end of the Late Devensian Cold Stage. Several types of limestone including Clifton Down Limestone, Cheddar Limestone and Cheddar Oolite are visible in the Gorge and surrounding areas with pale
Cheddar Gorge monuments as nationally important archaeological sites including: Gough's Old Cave, Great Oone's Hole, Saye's Hole, Soldier's Hole and Sun Hole. Cliff Road (B3135), which runs through the Gorge, offers a popular climb for bicyclists and has a maximum gradient of 16%. The ascent featured in stage 6 of the 2011 Tour of Britain. There are about 350 officially graded rock climbing routes on the 27 cliffs that make up Cheddar Gorge, which are generally open to climbers between 1 October and 15 March each year. Each of the routes is named and included in the British Mountaineering Council guidebook. Although