Angle Tarn (Langdale)




 * Not to be confused with Angle Tarn (Patterdale)

This particular Angle Tarn is probably the finest example of a cirque tarn in the Lake District. It’s almost circular form is encased by the rocky crags of Hanging Knott, that lies in a basin of volcanic rocks from the Borrowdale Volcanic Group. It is located at the head of Great Langdale at an elevation of 565 metres (1,854 feet) under the towering summit of Bowfell 902 metres (2,959 feet).

The distinctive shape of a cirque tarn usually includes three steeper sides, with the remaining open side to a moraine, a natural dam built of glacial debris, typically of unconsolidated rock, clay, silt, and sand. These moraines hold back the (sometimes) large volumes of water, controlled as an outflow in the form of a beck. Here, the outflow is Angletarn Beck. It is just one of many smaller tributaries of the larger Langstrath Beck, that flows parallel with part of the Cumbria Way. The water’s journey then continues by joining Stonethwaite Beck, then it passes through the Borrowdale Valley via Rosthwaite and, eventually, into the River Derwent and Derwentwater. Artist (1903 – 1995) had frequented Angle Tarn since childhood, and being familiar with the rocky features, describes the tarn and its water's journey with eloquence in his book, The Tarns of Lakeland: Here is a perfect combe tarn, carved from fine bedded volcanic ash, lying on the sunless side of the summit ridge of Bowfell, below the crags that were riven away in great blocks by the last remaining ice, and above the steep drop down to the valley of Langstrath. The ice left behind it deep moraines that fall steeply to the tarn except where the screes from hanging Knott do the same, and where the one small break in the sides of the bowl allows Langstrath Beck to start on its long and lovely way, over rock fall and through deep green slate-floored pool, to join the Derwent in Borrowdale on its journey through two lakes to the sea.

Cirque basins can also be very deep, created from the excavations of the, also known to British geologists as the Devensian Glaciation. Angle Tarn has a maximum depth of 16 metres (52½ feet), retaining a dark green, almost black hue from every side. It is fed from springs that seep through the scree, the water of which remains cold all year round. These "springs" are the becks from the encircling crags. Our map shows five distinct water courses flowing into the tarn, and popular aerial imagery defines these channels, which are the result of erosion over Millennia. Trout, though small of size owing to "not much feed with such a rocky floor" reside in the green depths.

Access to the tarn is via footpaths of varying difficulty. The Cumbria Way can be taken from Great Langdale, later joining another bridleway as it ascends Rossett Crag, before dropping down to the tarn on its eastern side. Continuing this bridleway will bring the walker to Sprinkling Tarn.