A caver in silhouette in the stream passage in Ogof Ffynnon Ddu, Brecon Beacons, south Wales

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This large stream passage is one of many in the complex cave system known as Ogof Ffynnon Ddu, on a nature reserve in the Swansea valley of south Wales, UK. The cave was first explored in 1946 and is now the third-longest cave in the UK, with more than 30 miles of surveyed passage. It is also the deepest cave in the UK. This passage lies beneath the headquarters of the South Wales Caving Club, the largest such club in Britain, with more than 300 members.

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Size: 3168px × 4752px
Location: Ogof Ffynnon Ddu, Brecon Beacons, south Wales, Powys, UK
Photo credit: © Anthony Baker / Alamy / Afripics
License: Licensed
Model Released: No

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