Lake Brienz (German: Brienzersee) is a lake just north of the Alps, in the Canton of Berne in Switzerland. It has a length of about 14 kilometres (8.7 mi), a width of 2.8 kilometres (1.7 mi) and a maximum depth of 260 metres (850 ft). Its area is 29.8 square kilometres (11.5 sq mi), and the surface is 564 metres (1,850 ft) above the sea-level. It is fed by the upper reaches of the Aar river at its eastern end and by the Lütschine river, flowing from the valleys of Grindelwald and Lauterbrunnen, at its south-western corner. It flows out into a further stretch of the Aar river at its western end.