Alnsjøen (also called Alunsjøen) is a lake in Lillomarka in

Oslo Oslo ( or ; ) is the capital and most populous city of Norway. It constitutes both a county and a municipality. The municipality of Oslo had a population of in 2022, while the city's greater urban area had a population of 1,064,235 in 2022 ...

, Norway. The lake is drained by the Alna River to the

Oslofjord The Oslofjord (, ; ) is an inlet in southeastern Norway. The fjord begins at the small village of Bonn in Frogn, Frogn Municipality and stretching northwards to the city of Oslo, and then curving to the east and then south again. It then flows s ...

. The surrounding area was utilized for

copper mining Copper extraction is the multi-stage process of obtaining copper from list of copper ores, its ores. The conversion of copper ores consists of a series of physical, chemical, and electrochemical processes. Methods have evolved and vary with coun ...

during the 18th century. The lake functions as a minor

water reservoir A reservoir (; ) is an enlarged lake behind a dam, usually built to store fresh water, often doubling for hydroelectric power generation. Reservoirs are created by controlling a watercourse that drains an existing body of water, interrupt ...

for the city of Oslo (the main water reservoir being the lake Maridalsvannet). File:Alunsjøen 09-01-02.jpg, Alnsjøen in winter File:Alunsjødammen.jpg, The dam of Alnsjøen

References

Lakes of Oslo {{Norway-lake-stub