Red Tarn is a small
lake
A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much lar ...
in the eastern region
of the English
Lake District, in the county of
Cumbria
Cumbria ( ) is a ceremonial and non-metropolitan county in North West England, bordering Scotland. The county and Cumbria County Council, its local government, came into existence in 1974 after the passage of the Local Government Act 1972. ...
. It is high up on the eastern flank of
Helvellyn
Helvellyn (; possible meaning: ''pale yellow moorland'') is a mountain in the English Lake District, the highest point of the Helvellyn range, a north–south line of mountains to the north of Ambleside, between the lakes of Thirlmere and ...
, beneath
Striding Edge and
Catstye Cam. Red Tarn was formed when the glacier that carved out the eastern side of Helvellyn had melted. The lake along with three others in Lake District is a habitat for the very rare and endangered
Schelly fish. Red Tarn was a dam in the nineteenth century that used boulders that raised the water level some eight or nine feet in order to supply power to the
Greenside Mine at Glenridding. Today the tarn is a popular rest stop for hikers and nature goers.

It lies at an altitude of 718 metres (2,356 feet), with a depth of 25 metres (82 feet).
The tarn is one of two of the same name in the Lake District. A second, much smaller Red Tarn lies between Pike of Blisco and Cold Pike, west of the Langdales.
References
Lakes of the Lake District
Patterdale
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