Bohuslän is a Swedish province in Götaland, on the northernmost part of the country's west coast. It is bordered by Dalsland to the northeast, Västergötland to the southeast, the Skagerrak arm of the North Sea to the west, and the county of Østfold, in Norway, to the north.
Bohuslän is named after the medieval Norwegian castle of Bohus. Under the name Baahuslen, it was a Norwegian county from the Norwegian conquest of the region from the Geats and subsequent unification of the country in the 870s until the Treaty of Roskilde in 1658, when the union of Denmark-Norway was forced to cede this county, as well as Skåneland to Sweden.
Coordinates 58°20'54.531" N 11°23'13.512" E