Between the reservoirs above Dolgarrog




7 miles (11.3kms)

500ft (152m)

About the walk

It was an ordinary Saturday evening in Dolgarrog, it had been raining hard for a few days, but in November that’s not so unusual.

Disaster in the hills

In the hills something was wrong. In the dark of night there were tremors in the ground and groans coming from the deep hollow of Eigiau. The reservoir dam was moving. Suddenly cracks appeared; then the unthinkable happened. The waters came thundering out through broken stone into the wide upper valley of the Afon Porth-llwyd, picking up speed towards the Coedty Reservoir. Would that hold? No, the dam disintegrated under the ever-increasing power of the flood. Boulders weighing over 200 tons were gouged from the mountainsides and thrust down in the raging torrents, and down further, towards the hapless village of Dolgarrog. Cottages lying in the way were smashed and the furnace at the aluminium works was engulfed, resulting in violent explosions. Dolgarrog was devastated.

Lost lives

Sixteen lives were lost that night in 1925. It is said that the death toll would have been higher were it not for the fact that many of the villagers and their children were at the cinema, which was on higher ground. An inquiry found that the dam had been built on insecure moraine debris from the last Ice Age, and had shifted under the pressure of the reservoir’s headwater. The dam was never rebuilt and the lake is now quite shallow, some 14ft (4.3m) lower than its previous level. From Dolgarrog you drive up a winding little road, through that narrow gorge, past the rebuilt cottages to arrive at the car park beneath the dam. Eigiau today is austere and rugged. You’re in a sombre, rushy basin deep in the Carneddau’s heartlands. The crags that rise out of this sad and shallow lake are precipitous. There’s a whitewashed cottage beneath a crag by the dam and another disused one up the valley. The view ends in the darkness of a steep grassy gully plummeting from the pass, Bwlch y Tri Marchog. The summit of Carnedd Llewelyn is hidden from here, though you’ll see it later from the other side of the valley, but Foel Grach, Foel-fras and Drum all look down on the scene from the western skies.

From the dam a pleasing road takes you back, the way the water would have gone, to Coedty Reservoir where you can look down to the Conwy Valley. You can still see the mess of boulders by the oak-shaded river banks, some ofthem undisturbed since that fateful evening.

Walk directions

Follow the track heading roughly southwest from the car park into the jaws of Eigiau. This turns left below the main dam and goes over a bridge across the reservoir’s outflow stream.

Turn left along the greener track that runs above and parallel to the river, ignoring the path ahead beneath Eilio. The gated track passes Coedty Reservoir and then leads to a country lane by the dam.

Follow the lane as it descends to cross the river, then climbs out onto the hillside high above the Conwy Valley.

Turn left at the T-junction to Rowlyn Isaf farm. The quickest and the recommended route follows the quiet country lane back to the car park.

Additional information

Tracks and country lanes, several stiles

Uncultivated moor, rough pasture and crag

Dogs should be on leads

OS Explorer OL17 Snowdon / Yr Wyddfa

Parking area at the end of the road

None on route

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About the area

Discover Conwy

The majority of the population of Conwy lives along its picturesque coastline, while a third of the county falls within jaw-dropping landscape of the Snowdonia National Park. The town of Conwy, which takes its name from the county (which in turn was named after the river that runs through it), is undoubtedly one of the great treasures of Wales.

Three fine bridges – Thomas Telford’s magnificent suspension bridge of 1822, Robert Stephenson’s tubular railway bridge, and a newer crossing – all stretch over the estuary beneath the castle, allowing both road and the railway into this medieval World Heritage Site. Pride of place goes to the castle, dating back to 1287.

Conwy is the most complete walled town in Britain, with walls measuring an impressive six feet in thickness and 35 feet in height. The walkway along the top offers splendid over-the-rooftop views of the castle, the estuary and the rocky knolls of nearby village of Deganwy. At the wall’s end, steps descend to the quayside where fishermen sort their nets and squawking seagulls steal scraps.

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