Glaslyn 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,...

 in the Snowdonia National Park in Gwynedd

Gwynedd

Gwynedd is a county in north-west Wales, named after the old Kingdom of Gwynedd. Although the second biggest in terms of geographical area, it is also one of the most sparsely populated...

, north-west Wales

Wales

Wales is a country that is part of the United Kingdom and the island of Great Britain, bordered by England to its east and the Atlantic Ocean and Irish Sea to its west. It has a population of three million, and a total area of 20,779 km²...

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It is found at approximately 600 metres (1,968.5 ft) above sea level

Above mean sea level

The term above mean sea level refers to the elevation or altitude of any object, relative to the average sea level datum. AMSL is used extensively in radio by engineers to determine the coverage area a station will be able to reach...

 in a cwm

Cirque

Cirque may refer to:* Cirque, a geological formation* Makhtesh, an erosional landform found in the Negev desert of Israel and Sinai of Egypt*Cirque , an album by Biosphere* Cirque Corporation, a company that makes touchpads...

 on the eastern flanks of Snowdon

Snowdon

Snowdon is the highest mountain in Wales, at an altitude of above sea level, and the highest point in the British Isles outside Scotland. It is located in Snowdonia National Park in Gwynedd, and has been described as "probably the busiest mountain in Britain"...

. It is a rough ellipse in shape, about 500 metres (1,640.4 ft) east–west and about 300 metres (984.3 ft) north–south, and the Miners' Track runs along the northern shore.

Glaslyn is the source of the Afon Glaslyn

River Glaslyn

The Afon Glaslyn is a river in Gwynedd, north-west Wales. Whilst not of great significance in terms of its length , it is one of Gwynedd's primary rivers, and has greatly influenced the landscape in which it flows....

, the major river of Gwynedd, which runs east to the reservoir of Llyn Llydaw

Llyn Llydaw

Llyn Llydaw is a lake in Snowdonia National Park on the flanks of Snowdon, Wales' highest mountain. This long thin lake has formed in a cwm about one-third of the way up the mountain....

 before turning south-west to reach the sea at Porthmadog

Porthmadog

Porthmadog , known locally as "Port", and historically rendered into English as Portmadoc, is a small coastal town and community in the Eifionydd area of Gwynedd, in Wales. Prior to the Local Government Act 1972 it was in the administrative county of Caernarfonshire. The town lies east of...

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