Akerselva, or Akerselven, is a river which flows through Oslo. It starts at Maridalsvannet in Oslomarka, and follows the urban areas Nordre Aker, Sagene, Grünerløkka, Oslo centre and Grønland, whereby it finally ends at Paulsenkaien and Oset in Bjørvika. The river is considered to be a part of the Nordmarkvassdraget, and has the watercourse number 006.Z.