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Cave or grotto

Porth yr Ogof

Near Ystradfellte, Powys

Wales's biggest cave mouth, where a river disappears.

The River Mellte vanishes into Porth yr Ogof, 'the gateway to the cave', which has the largest cave entrance in Wales. Inside is a pool with a streak of white calcite on the wall shaped like a horse, the White Horse.

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When
Natural
Where
51.8000, -3.5560
Group
Caves & grottoes

Visiting

A short walk from the car park. Only enter with experienced cavers.

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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