Llyn Cwm Llwch
Encyclopedia
Llyn Cwm Llwch 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 Brecon Beacons National Park in Powys
Powys
Powys is a local-government county and preserved county in Wales.-Geography:Powys covers the historic counties of Montgomeryshire and Radnorshire, most of Brecknockshire , and a small part of Denbighshire — an area of 5,179 km², making it the largest county in Wales by land area.It is...

, 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...

. It is a small lake of glacial origin occupying a rock hollow beneath the peaks of Pen y Fan
Pen y Fan
Pen y Fan is the highest peak in South Wales and southern Britain, situated in the Brecon Beacons National Park. At above sea-level, it is also the highest peak in Britain south of the Snowdonia mountain range...

 and Corn Du
Corn Du
Corn Du is a mountain immediately to the southwest of Pen y Fan and the second highest peak in South Wales, situated in the Brecon Beacons National Park. Tommy Jones' Obelisk is found on its western flanks, in between the summit and Y Gyrn....

 in the central Brecon Beacons
Brecon Beacons
The Brecon Beacons is a mountain range in South Wales. In a narrow sense, the name refers to the range of popular peaks south of Brecon, including South Wales' highest mountain, Pen y Fan, and which together form the central section of the Brecon Beacons National Park...

. It is drained by the Nant Cwm Llwch which empties into the Afon Tarell which itself enters the River Usk
River Usk
The River Usk rises on the northern slopes of the Black Mountain of mid-Wales, in the easternmost part of the Brecon Beacons National Park. Initially it flows north into Usk Reservoir, then east by Sennybridge to Brecon before turning southeast to flow by Talybont-on-Usk, Crickhowell and...

 at Brecon
Brecon
Brecon is a long-established market town and community in southern Powys, Mid Wales, with a population of 7,901. It was the county town of the historic county of Brecknockshire; although its role as such was eclipsed with the formation of Powys, it remains an important local centre...

.
Tommy Jones' obelisk, a memorial in granite to a young boy who died near this spot many years ago, overlooks the lake.

Geology

The lake occupies a hollow excavated in the sandstones of the Brownstones Formation of the Old Red Sandstone
Old Red Sandstone
The Old Red Sandstone is a British rock formation of considerable importance to early paleontology. For convenience the short version of the term, 'ORS' is often used in literature on the subject.-Sedimentology:...

 by glacial action during the succession of recent ice ages. Its northern margins are rimmed by an arcuate late-glacial moraine
Moraine
A moraine is any glacially formed accumulation of unconsolidated glacial debris which can occur in currently glaciated and formerly glaciated regions, such as those areas acted upon by a past glacial maximum. This debris may have been plucked off a valley floor as a glacier advanced or it may have...

.

Access

The lake is within open country and readily accessible to walkers. A popular path up to Pen y Fan runs up Cwm Llwch from Llwynybedw, passing by the outlet of the lake. It is seen to advantage from the peaks of both Pen y Fan and Corn Du and indeed from the spur of Pen Milan to its west.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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