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Cave or grotto

Ogof Ffynnon Ddu

Penwyllt, Powys

The deepest cave in the UK.

Ogof Ffynnon Ddu, 'Cave of the Black Spring', was discovered in 1946. It runs for over 50 kilometres under the Brecon Beacons and is around 274 metres deep, the deepest cave in the UK.

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When
Found 1946
Where
51.8120, -3.6630
Group
Caves & grottoes

Visiting

Not open to the public. Dan yr Ogof show caves are nearby.

Cover of The Ledger of Lost Britain by Cale Mills
Read the full story in the book

The Ledger of Lost Britain

The Romans arrived in AD 43. For most people that is where the history of Britain begins. But by the time the legions landed, people had already been living on these islands for thousands of years. They had hunted, farmed, mined flint, dragged stones across the country, raised a hill by hand, and buried their dead in great tombs. They left no written words. What they left was the ground itself. Every place in this book can be visited, or has been dug up, or is in a museum.

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