Llyn Dulyn is a lake

Lake

A lake is a body of relatively still fresh or salt water of considerable size, localized in a basin, that is surrounded by land. Lakes are inland and not part of the ocean and therefore are distinct from lagoons, and are larger and deeper than ponds. Lakes can be contrasted with rivers or streams,...

 on the edge of the Carneddau

Carneddau

The Carneddau , are a group of mountains in Snowdonia, Wales. It includes the largest contiguous areas of high ground in Wales and England, as well as six or seven of the highest peaks in the country—the Fourteen Peaks...

 range of mountains in Snowdonia

Snowdonia

Snowdonia is a region in north Wales and a national park of in area. It was the first to be designated of the three National Parks in Wales, in 1951.-Name and extent:...

, North Wales

North Wales

North Wales is the northernmost unofficial region of Wales. It is bordered to the south by the counties of Ceredigion and Powys in Mid Wales and to the east by the counties of Shropshire in the West Midlands and Cheshire in North West England...

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The lake covers an area of only 33 acres (133,546.4 m²), yet is extremely deep - it reaches to a depth of 189'. Less than a kilometre to its south lies the smaller Llyn Melynllyn

Llyn Melynllyn

Llyn Melynllyn is a lake on the edge of the Carneddau range of mountains in Snowdonia, North Wales.It lies at a height of just over , and has an area of some ....

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Cliffs rise steeply from the lake edge up to the summits of Garnedd Uchaf

Garnedd Uchaf

Garnedd Uchaf is a minor summit of the Carneddau range in Snowdonia, Wales, and included in the Welsh 3000s. From the summit, distant views to the north can extend as far away towards Ireland and the Isle of Man, whereas to the South, views can extend as far South towards the Berwyn Ranges.It...

 and Foel Grach

Foel Grach

Foel Grach is a mountain in the Carneddau range, is the eighth highest summit in Snowdonia as well as Wales, and therefore included the Welsh 3000s....

, giving it a dark brooding appearance - hence its name. A number of superstitions are connected with the cwm, which has also been the site of a number of small aeroplane crashes.

The lake has a dam, originally built in 1881, to increase its water capacity, but it has been altered several times since. As a reservoir Dulyn (along with Melynllyn) provides water for the town of Llandudno

Llandudno

Llandudno is a seaside resort and town in Conwy County Borough, Wales. In the 2001 UK census it had a population of 20,090 including that of Penrhyn Bay and Penrhynside, which are within the Llandudno Community...

. The pipes cross the River Conwy

River Conwy

The River Conwy is a river in north Wales. From its source to its discharge in Conwy Bay it is a little over long. "Conwy" is sometimes Anglicized as "Conway."...

 at Tal-y-Cafn

Tal-y-Cafn

Tal-y-Cafn is a small settlement in Conwy county borough, north Wales.It lies in the Conwy valley close to the Roman settlement of Canovium at Caerhun, and was the site of a Roman river-crossing point of the River Conwy...

 bridge.

The outflow from the lake is called Afon Dulyn

Afon Dulyn

Afon Dulyn is the outflow from Llyn Dulyn, a lake in the Carneddau mountains in North Wales. It is a tributary of the river Conwy....

, and this stream also feeds water into neighbouring Llyn Eigiau

Llyn Eigiau

Llyn Eigiau is a lake on the edge of the Carneddau range of mountains in Snowdonia, North Wales.The name Eigiau is thought to refer to the shoals of fish which once lived here. Early maps refer to it as Llynyga...

. Afon Dulyn flows north-east, passing Tal-y-bont

Tal-y-bont, Conwy

Tal-y-Bont is a small village in Conwy County Borough, Wales. It lies in the Conwy Valley in North Wales, west of the River Conwy, on the B5106 road, six miles from Conwy to the north, and six miles from Llanrwst to the south....

 before joining the River Conwy

River Conwy

The River Conwy is a river in north Wales. From its source to its discharge in Conwy Bay it is a little over long. "Conwy" is sometimes Anglicized as "Conway."...

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