or is a

lake A lake is often a naturally occurring, relatively large and fixed body of water on or near the Earth's surface. It is localized in a basin or interconnected basins surrounded by dry land. Lakes lie completely on land and are separate from ...

and

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

Hattfjelldal Municipality or is a municipality in Nordland county, Norway. It is part of the Helgeland traditional region. The administrative centre of the municipality is the village of Hattfjelldal. Other villages include Grubben, Svenskvollen, and Varntresk. Hat ...

and

Hemnes Municipality Hemnes is a List of municipalities of Norway, municipality in Nordland Counties of Norway, county, Norway. It is part of the Helgeland Districts of Norway, traditional region. The administrative centre of the municipality is the village of Korgen ...

Nordland Nordland (; , , , ) is one of the three northernmost Counties of Norway, counties in Norway in the Northern Norway region, bordering Troms in the north, Trøndelag in the south, Norrbotten County in Sweden to the east, Västerbotten County to t ...

county,

Norway Norway, officially the Kingdom of Norway, is a Nordic countries, Nordic country located on the Scandinavian Peninsula in Northern Europe. The remote Arctic island of Jan Mayen and the archipelago of Svalbard also form part of the Kingdom of ...

. It has been the site of human occupation since the

Stone Age The Stone Age was a broad prehistory, prehistoric period during which Rock (geology), stone was widely used to make stone tools with an edge, a point, or a percussion surface. The period lasted for roughly 3.4 million years and ended b ...

. Its area of makes it the second largest lake in Norway by surface area. Without the

dam A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use, aqua ...

which has regulated the lake since 1957, it would be and the third largest lake in Norway. Its depth is , its volume is estimated at , and its surface elevation is above sea level.

Røssvassholmen

The island Røssvassholmen is located in the southern part of the lake. it is the largest island in the lake. The highest point on the island reaches above the lake's surface (at top regulation height). The island is Norway's second largest lake-island. The largest island within a lake in Norway is Helgøya, located within the lake

Mjøsa Mjøsa is the largest lake in Norway and the fourth deepest in Norway and Europe. It is located in the southern part of Norway, about north of the city of Oslo. Its main tributary is the river Gudbrandsdalslågen flowing in from the north; the ...

References

External links

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Archeological article
(in Norwegian) (URL accessed 7 April 1983) Lakes of Nordland Hattfjelldal Hemnes Reservoirs in Norway {{Nordland-geo-stub