Sværsvann
Sværsvann is a lake in the southeast of Oslo, Norway. The lake drains off into the river Hobølelva. The lake's surrounding areas are mostly residential. Sværsvann is a popular bathing place, and the name is believed to origin from "Sværd Vandet", which means "Sword Water", because a sword was once found at the bottom of the lake. The bottom water contains huge amount of salts, organic nutrition and hydrogen sulfid.
Coordinates: 59°49′01″N 10°53′23″E / 59.81694°N 10.88972°E
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