Martyn Farr (born Crickhowell, Wales, March 3, 1951) is a leading exploratory cave diver and caver, known for his record-breaking cave dives and the exploration of many miles of previously undiscovered underground passages (e.g. in Ogof y Daren Cilau and Noon's Hole). As an author and photographer he has written many books on the subject of cave diving history and techniques and caving locations.
Farr began caving in 1961 and cave diving in 1971, and within 10 years had established a world record for underwater cave penetration in the Bahamas. He is noted within the cave diving community for his explorations in Wookey Hole in 1977 and 1982, and for completing the first traverse of Llangattock Mountain in Wales in 1986, the execution of which was a televised media event, being the longest and deepest caving through trip in the British Isles. In 1978, Farr discovered also the Pollatoomary cave in the Partry Mountains of the Republic of Ireland. In 2008, his student Artur Kozłowski explored this cave to a depth of 103 metres, which made it the deepest known cave on the British Isles.
As well as running a cave diving training facility in South Wales, Farr is a regular contributor to diving magazines around the world. Farr has also acted as support diver in some of the world's most notable cave diving penetrations, including the British-led expedition to Pozo Azul in Spain in September 2010, which at 8.8 km (5.5 miles) of underwater travel is the world's longest cave diving penetration.
- The Darkness Beckons - The History And Development Of Cave Diving (1980)
- The Great Caving Adventure (1984)
- Wookey: The Caves Beyond (1985)
- Darkworld - The Secrets Of Llangattock Mountain (1997)
- The Secret World Of Porth yr Ogof (1998)
- Dan yr Ogof: The Jewel Of Welsh Caves (1999)
- Underground Wales (2001)
- Diving In Darkness - Beneath Rock, Under Ice, Into Wrecks (2003)
- Cave Diving Group History 1970 - 1979
- Irish Times article referencing Farr's records for longest and deepest sump dives in Ireland in the 1980s
- Daily Mail article: Incredible Pictures from Britain's Best Cave Diver
- Books by Martyn Farr
- Siggins, Lorna (7 September 2011). "'There is no rescue - only recovery, if you're lucky'". Irish Times. Retrieved 27 June 2012.
- Interview with Martyn Farr in Advance Diver Magazine (US)
- Martyn Farr writes about diving the caves beneath Australia's Nullarbor Plain in Diver Magazine (UK)
- The world's longest cave diving penetration
- Support diver Martyn Farr writes about the world record Pozo Azul cave diving penetration
- The Darkness Beckons "has achieved legendary status" - Diver Magazine (UK)