Discover Somerset and Explore the Fossils and Geodiversity of Banwell Caves
- Wayne Munday
- 6 days ago
- 4 min read
Updated: 6 minutes ago
Sip back and discover Somerset and explore the fossils, Ice Age fauna and the unique geology of Banwell Caves in Somerset’s Mendip Hills a hidden SSSI rich in history and karst features. Located at the western edge of Banwell Hill in North Somerset and just 10 Km from Weston-super-Mare these caves tell a story starting over 350 million years ago during the Dinantian Epoch of the early Carboniferous period up to the Pleistocene where a 80,000 discover-somerset-and-explore-the-fossils-and-geodiversity-of-geodiversityyear old fossil assemblage of Ice Age megafauna bones from the Early Devensian period rest. Somerset at this time was a cold, tundra-like environment inhabited by bison, reindeer, brown bear, arctic fox, wolverine, and wolf, as well as rarer elephants, woolly rhinoceroses and cave lions. Banwell Caves are thought to have been a natural pitfall trap where animal bones gradually accumulated through groundwater flooding. Banwell Caves is not open to the public and is now a private residence. More information maybe available from the Mendip Hills National Landscape a designated Area of Outstanding Natural Beauty (AONB).
The original Stalactite Cave at Banwell Caves was discovered in 1757 but proved to be too dangerous to access but further exploration by miners John Webb and Isaac Colman between 1824 - 1826 of a lower fissure unexpectedly opened up and led to the discovery of the Banwell Bone Cave.
By the early 19th century, Bishop George Henry Law and local vicar Dr Randolph decided upon the idea of developing Banwell Caves located on Law’s land to raise funds for a new charity school through collections from guided tours. This initially transformed Banwell Caves into an early Victorian show cave attraction up and until 1840.
The Banwell Caves should not be confused with the Banwell Ochre Caves only a few miles west on the A368 towards Banwell Woods. The Banwell Ochre Caves are among the most important and accessible yellow ochre mining sites in the region formed naturally within steeply dipping Carboniferous Limestone through phreatic or water-filled cave-forming processes that occur below the water table where rock voids are fully saturated. Under hydrostatic pressure the groundwater dissolves the limestone to form cave passages where minerals settle.
The Banwell Ochre Caves contain a diverse range of ochre types and iron hydroxides or limonites are visible as residual ore bodies linked to Pleistocene (Ice Age) sediments. Their presence highlights significant mineral accumulation during past climatic changes. Ochre extraction took place from the 1930s until 1948. Remnants of this past mining activity still remain offering insight into its historical use. The ochre mineralisation across the Mendip Hills is believed to have originated from the weathering of iron-rich rocks during the Permian and Triassic periods with iron transported by groundwater and redeposited in the limestone.
During the Carboniferous Period the United Kingdom was nearer to the equator and was submerged beneath the tropical Rhetic Ocean a major Paleozoic sea located between Laurentia and Gondwana. This was a time when a warm, shallow tropical sea covered vast areas of the country creating the perfect conditions for a rich marine ecosystems to thrive. Coral reefs flourished alongside brachiopods and crinoids and as these sea creatures died their remains settled on the seabed. Layer upon layer, over millions of years their skeletal fragments compressed and solidified to form what we now know as Carboniferous Limestone.
During the Carboniferous Period significant limestone accumulation began to happen across the UK forming what is defined as the Carboniferous Limestone Supergroup. This Carboniferous Limestone Supergroup was extensively deposited across England and Wales between the Tournaisian Age and Viséan Age an interval of 28 million years from 358.9 - 330.9 million years ago. Members of the Carboniferous Limestone Supergroup are present in the south and west of Cumbria, the Yorkshire Dales, North and South Wales, the Peak District and underlays much of the Bristol and Mendip Hills.
As these continents collided and the Rhetic Ocean closed, tectonic forces uplifted submerged rock, including the Carboniferous Limestone found at places such as Banwell Caves, Cheddar Gorge and generally the wider the Mendip Hills. Subsequent erosion over millions years shaped this landscapes vast underground karst system visible today.
The Mendip Hills in Somerset is one of the most striking examples of a classic karst landscape in the United Kingdom. Carved over millions of years this terrain has been shaped by the natural process of karstification or the dissolution of Carboniferous Limestone by slightly acidic rainwater.
As water percolates through cracks, joints, and bedding planes in the rock, it gradually enlarges them, forming a complex and dynamic system of surface and subterranean features that define the region's dramatic topography. Below the surface, water continues its path and sculpts vast cave systems and underground rivers that crisscross the limestone bedrock. The Mendip Hills are known for their extensive and varied cave systems including the largest underground river system in Britain.
The Banwell Caves maybe known for the Ice Aged Banwell Type Fauna but it is also a protected wildlife sanctuary providing a hibernation site or a hibernaculum offering winter refuge from cold weather and predators for the rare and endangered species of Greater Horseshoe Bat (Rhinolophus ferrumequinum).
