St Cuthbert's Swallet

St Cuthbert’s Swallet is a deep cave beneath the Mendip Hills in Somerset. It lies under the Priddy Pools Site of Special Scientific Interest and drains water that later appears at Wookey Hole. The cave was first named St Cuthbert’s Pot before explorers gained entry in the 1950s. Early attempts to find an entrance began before 1927 when St Cuthbert’s Pool suddenly emptied. Exploration pushed further limits through the 1950s and 1960s, though the second sump remains unpassed. Access is controlled by the Bristol Exploration Club due to a 19th-century injunction protecting water purity. The cave reaches over six kilometres long and plunges 145 metres deep. It contains seven levels of fault-guided rifts and large decorated chambers formed over nine phases of sediment and erosion. Notable features include Gour Hall with its six-metre gour, the ‘Curtains’ and ‘Cascade’ calcite formations, and the ‘Balcony’ in September Chamber. Small formations such as cave pearls and delicate fern-like crystals add to its detail. Scientists study cave insects here, including a tiny springtail species first collected in 1969. Visitors cannot enter without permission from the Bristol Exploration Club. The cave’s controlled access preserves its scientific and geological importance. Its complex passages and decorated chambers remain a focus for cavers and researchers. The site records environmental changes from Ice Age warm and cold phases. Its rare formations and cave life make it a key location for study. The cave’s history and depth continue to draw attention from explorers and scientists alike.