Wookey Hole
Mendip Cave Registry entry, last updated 2024-03-02. 143 m is the Mendip Cave Registry's overall depth (vertical range) for the cave. The deepest point reached by divers is 90 m (2004-2005, CDG); the registry also notes Sump 25 dived to -210 ft (about 64 m).
A show cave in the Mendip Hills whose flooded river passages are the birthplace of British cave diving. Cave Diving Group divers pushed it to a 90 m British depth record in 2004-2005; no public diving access is published.
Wookey Hole is a commercial show cave in Somerset, and its operators describe it as the birthplace of British cave diving. Divers began pushing beyond the dry chambers in the 1930s, revealing chambers that were previously unknown; the Cave Diving Group (CDG), founded in 1946 by the pioneer Graham Balcombe, grew out of this work.
Its chambers are known by numbers (for example Chamber 20), and many are separated by flooded sections called sumps. The far reaches, including the large Chamber 20, were explored by CDG divers; Chamber 20 was opened to show-cave visitors in 2015 after a 70 m tunnel was blasted through the rock.
The deep sump beyond has been the scene of several British depth records: about 60 m on compressed air in the early 1980s (Martyn Farr with Rob Palmer and Rob Parker), 68 m by Rob Parker on trimix in 1985, and 90 m in 2004-2005 by a team led by Rick Stanton and John Volanthen using sidemount closed-circuit rebreathers.
The Mendip Cave Registry lists the cave at 3,659 m long with a vertical range of 143 m, and holds 28 historic surveys dating from 1904 to 1969. Archaeological remains of Romano-British age, including human remains, have been found in the cave.
Why it matters
Birthplace of British cave diving and of the Cave Diving Group; site of successive British cave-diving depth records up to 90 m (2004-2005).
Survey and exploration history
| 1935 | Balcombe and others publish 'The Great Cave of Wookey Hole' survey after the early diving work. [2] |
| 1946 | Graham Balcombe founds the Cave Diving Group. [3] |
| 1969 | The CDG produces its survey of Wookey '20'. [2] |
| 1985 | Rob Parker reaches 68 m using trimix, ending at a gravel slope. [4] |
| 2004 | A team led by Rick Stanton and John Volanthen begins dives that reach 90 m by 2005, a British depth record. [4] |
| 2015 | Chamber 20, formerly reached only by divers, is opened to show-cave visitors via a blasted 70 m tunnel. [1] |
Entrances and dive sites
The show-cave entrance in the Wookey Hole ravine; the Mendip Cave Registry also lists Wookey Hole Spring and several artificial tunnels and culverts as separate features.
No individual entrances are listed for this system yet.
For orientation, not navigation. Hollow dots are approximate.
Further reading
British Cave Research Association (BCRA) ↗
Cave Diving Group Manual ↗
Somerset Sump Index 2008 ↗
The Darkness Beckons ↗
The Log of the Wookey Hole Exploration Expedition ↗
Wookey Hole: 75 Years of Exploration ↗
Every fact on this page, with its source (8)
| Fact | Status | Source |
|---|---|---|
| The Mendip Cave Registry lists Wookey Hole at 3,659 m long.Registry record updated 2024-03-02. | Verified | [2] |
| The registry gives an overall depth of 143 m.The registry does not explain how this vertical range is made up; the CDG gives 90 m as the diving depth record. | Reported | [2] |
| Divers reached about 60 m on air in the early 1980s, 68 m on trimix in 1985 (Rob Parker), and 90 m in 2004-2005 (team led by Rick Stanton and John Volanthen), a British depth record. | Verified | [4] |
| Chamber 20, previously reached only by cave divers, was opened to the public in 2015 after a 70 m tunnel was blasted. | Verified | [1] |
| The CDG was founded in 1946 by Graham Balcombe; the show cave calls Wookey 'the birthplace of British cave diving'. | Verified | [3] [1] |
| The operator's site describes a show cave with guided or self-paced tours and publishes no cave-diving access arrangements.Absence of a published arrangement, not a confirmed ban. | Verified | [1] |
| Romano-British remains, including human remains, were found in the cave; its farthest reaches, including Wookey 20, were explored by the CDG. | Verified | [2] |
| The registry gives WGS84 coordinates 51.22933, -2.67176 (ST 53191 48008) for the cave.Public show-cave entrance. | Verified | [2] |
Verified: stated by an official or primary source we opened. Reported: from a secondary source only. Sources conflict: the note gives both versions. May be out of date: the newest source we found is old.
Written in our own words from the sources above. Report a correction