Submerged valley
Nantgwyllt House
Nantgwyllt House was demolished and now lies under Caban Coch Reservoir. The original house of the Powell family was of grey stone, long and…
Read the storyLost beneath the reservoirs • Elan Valley
Elan Valley historical archiveThe Submerged Valley
Beneath the waters lie the remains of homes, churches, work sites and an entire landscape. Discover the stories of the Elan Valley before the reservoirs.
Discover the placesBefore the reservoirs
Lives and places beneath the water
Explore a collection of historic sites submerged or altered by the reservoir construction. These photographs and records preserve the memory of buildings that once stood along the valley floor.
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See the illustrated archive →Places beneath the water
Open each location for its history and photographs.
Submerged valley
Cwm Elan House
The estate of Cwm Elan, containing the Elan Valley mansion, was purchased in 1792 by Thomas Grove. It was described then as “10,000 worthless…
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Submerged valley
Cwm Elan Lodge
Cwm Elan Lodge was located in Cwm Elan and is now submerged beneath Garreg Ddu Reservoir. Photos courtesy of Mary Connelly Map Ref SN91071 64315
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Submerged valley
Garreg Ddu
Remains of Garreg Ddu before the dams and what still remains today. Map Ref SN91032 63861
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Rural structures
Garreg Ddu Navvy Huts
Site of Garreg Ddu Navvy Huts. Normally submerged under Caban Coch Reservoir. Map Ref SN
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Submerged valley
Baptist Chapel
The Baptist Chapel, now submerged beneath Caban Coch Reservoir. Map Ref SN91070 63929
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Houses & farms
Pant y Blodau
Pant y Blodau was a small house, now submerged beneath Caban Coch Reservoir. Map Ref SN91734 62678
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Houses & farms
Dol-folau
Dol-folau before the valley was flooded, together with later photographs of the remains when water levels were low. Map Ref SN91331 65648
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Houses & farms
Ty Nant, Elan Valley
Remains of Ty Nant House under Pen y Garreg Reservoir. Map Ref SN9019 6727
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Submerged valley
Nant Gwyllt Church
Nant Gwyllt Church, submerged under Caban Coch Reservoir. It was a small church. Map Ref SN91809 63939
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Houses & farms
Lluest Tor-Clawdd House
Small hill farm now submerged by Craig Goch Reservoir. Map Ref SN89560 70400
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Houses & farms
Dol-Faenog House
Dol-Faenog House, now under Pen y Garreg Reservoir. Map Ref SN91580 66820
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Houses & farms
Cwm Coel House
Site of Cwm Coel House, not much to see. Normally under Garreg Ddu. It was a farmhouse with a tall chimney. Map Ref SN9062 6413
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Houses & farms
Gro Isfa
Remains of Gro Isfa under Caban Coch Reservoir. Map Ref SN92080 63640
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Houses & farms
Gro Uchaf
Gro Uchaf before the valley was flooded. The barn on the right was moved to Clearwen Farm. Map Ref SN91764 63068
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Houses & farms
Gro Bach
Remains of Gro Bach under Caban Coch Reservoir. Map Ref SN92060 63560
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Submerged valley
Nant Gwyllt Cottages
Possibly the remains of Nant-gwyllt Cottages, photographed on 10/08/2022. Unfortunately there are no known earlier photographs here from before…
Read the storyIndustrial heritage
Nant Gwyllt Cottages
Possibly the remains of Nant-gwyllt Cottages, photographed on 10/08/2022. Unfortunately there are no known earlier photographs here from before…
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Industrial heritage
Stone Dressing Yard
The Stone Dressing Yard before the valley was flooded. Map Ref SN913 646
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Industrial heritage
Old Construction Shed
Old construction shed near Craig Goch Dam, with the old railway lines still visible. Map Ref SN89220 68716
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Industrial heritage
Old Foot Bridge
Old footbridge under Craig Goch Reservoir, not far from the Hirnant. It is called Pontbren Lloc-ddu and is locally known as Pwll Coon. Photo…
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Industrial heritage
Nanty Postdy Bridge
Nanty Postdy Bridge, also known as Horse Bridge. Remains of an old bridge just downstream of Dolymynach Dam, normally submerged under Caban…
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Industrial heritage
Gro Walls
Walls, footpaths and a bridge normally submerged under Caban Coch Reservoir.
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All ruins & lost places →More of the valley's lost history
Browse abandoned farmhouses, sheepfolds and other ruins across the hillsides.
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Explore the Elan Valley on the map
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