Llyn Cowlyd

Llyn Cowlyd
View looking north-east down the length of the lake
Llyn Cowlyd
Location	Snowdonia National Park, Wales
Coordinates	53°08′N 3°55′W / 53.133°N 3.917°W / 53.133; -3.917
Type	natural lake, reservoir
Basin countries	United Kingdom
Surface area	1.1 square kilometres (271.8 acres)
Average depth	33 m (108 ft)
Max. depth	70 m (230 ft)
Surface elevation	355 m (1,165 ft)

Llyn Cowlyd is the deepest lake in northern Wales. It lies in the Snowdonia National Park at the upper end of Cwm Cowlyd on the south-eastern edge of the Carneddau range of mountains, at a height of 330 metres (1,083 ft) above sea level. The lake is long and narrow, measuring nearly 3 kilometres (2 mi) long and about 500 m (third of a mile) wide, and covers an area of 1.1 square kilometres (271.8 acres). It has a mean depth of 33 metres (108 ft) and at its deepest has given soundings of 70 metres (230 ft), this being some 14 m (46 ft) greater than its natural depth, the water surface having been raised twice by the building of dams.^[1]

The surrounding hills drop steeply to the water's edge, from Cefn Cyfarwydd and Creigiau Gleision to the east, and Pen Llithrig y Wrach to the west, and as a consequence have not been forested in the 20th century, as were the slopes of neighbouring Llyn Crafnant. Indeed, there is not a tree to be seen, and the general aspect is one of bleakness. Dependent on the weather conditions, the waters often appear dark.

The supply of water to Llyn Cowlyd is assisted at its south-western end by a leat which runs roughly east–west along the 418m contour to the south and west of the lake, along the Llugwy valley. It is also fed by water from Llyn Eigiau.

Llyn Cowlyd can be reached by road from Trefriw, some 5 kilometres (3 mi) to the east, although the metalled road stops at a gate, the best part of a mile from the lake itself, beyond which private vehicles are not permitted. Llyn Cowlyd can also be reached by foot from Capel Curig, some 5 kilometres (3 mi) away, from the ridge of Cefn Cyfarwydd, or from above Dolgarrog. A good path runs along the north-western shore of the lake.

The stream which flows from Llyn Cowlyd is called Afon Ddu. This flows into the river Conwy, passing Pont Dolgarrog on the B5106 road, just south of the village of Dolgarrog. The gorge cut by the river at this point is popular for gorge walking.