Lake Brienz (German: Brienzersee) is a lake just north of the Alps, in the Canton of Berne in Switzerland. The lake took its name from the village Brienz on its northern shore. Interlaken and the villages Matten and Unterseen lie to the south west of the lake. The shores are steep, and there is almost no shallow water in the entire lake.
Lake Brienz is the first lake in which river Aar (German: Aare) expands. When it leaves Lake Brienz, it soon joins Lake Thun.
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| Lake Brienz from Rothorn | | Lake Brienz |
The lake lies in a deep hollow between the village of Brienz on the east and, on the west, Bönigen, close to Interlaken. Its length is about 9 miles, its width 1½ miles, and its maximum depth 856 feet, while its area is 11½ square miles, and the surface is 564 metres (1,850 ft) above the sea-level. On the south shore are the Giessbach Falls and the hamlet of Iseltwald. On the north shore are a few small villages. The character of the lake is gloomy and sad as compared with its neighbour, that of Thun. Its chief affluent is the Lütschine (flowing from the valleys of Grindelwald and Lauterbrunnen).
The lake is poor in nutritients, and consequently fishing is not very important. Nevertheless, in 2001 10,000 kg fish were caught. There have been passenger ships on the lake since 1839. The ships are operated by BLS Lötschbergbahn, the local railway company. There are five passenger ships on the lake.
