Location Hovedstaden region Primary outflows Arresø Canal Surface area 40.72 km (15.72 sq mi) Area 39.87 km² Mean depth 3.1 m | Primary inflows Average depth 3.1 m (10 ft) Surface elevation 3.9 m Catchment area 216.1 km² | |
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Cities Frederiksværk, Ølsted, Halsnæs Municipality, Ølsted | ||
Arresø is the largest lake, based on area, in Denmark. Arresø covers 40,72 km² (15.39 sq mi) and is situated on the island of Zealand.
Map of Arres%C3%B8, Denmark
Arresø is located in the northern parts of Zealand in the region of Hovedstaden just north of Ølsted and east of Frederiksværk. The lake empties into Roskilde Fjord through the Arresø Canal in Frederiksværk. The artificial canal was begun around 1717 by royal command, and the work was carried out by Danish soldiers and Swedish POW's.
There are a number of rivers and streams running into Arresø of which the Pøleå is the most significant. The landscape is especially hilly along the lake's west side. Among these ridges are Maglehøj in the town of Frederiksværk and Arrenakke Hills, which offers a magnificent view of the lake. East of Frederiksværk, the Arrenæs peninsula juts out into the lake.
Historically, Arresø was a fjord, connected to the Kattegat, but the land northwest of here rose after the last Ice Age, locking the waters in and creating the lake.
Arresø has a rich bird and floral life. Sea eagles have returned as nesting birds, and beavers have been reintroduced. Several wildlife preserves have been set up around the lake and it will also form part of national park Royal North Sealand currently being planned and established in North Zealand.
Th renovated wooden ship of M/S Frederikke, offers boat tours on the lake between May and September, embarking from Arresødal.