Smedjebacken is a locality and the seat of Smedjebacken Municipality, Dalarna County, Sweden, with 5,100 inhabitants in 2010. Geographically, the town Smedjebacken is situated by the lake Barken, with an area of 34 km2, which in turn belongs to the Kolbäcksån stream-system, which drains into lake Mälaren to the south-east.