Nordsøen Oceanarium is a public aquarium and museum that opened in 1998 on the shores of the North Sea in Hirtshals, north Jutland, Denmark. Their main tank, which holds 4500000l, is the largest in Northern Europe, but the Oceanarium also has several smaller habitat aquariums and an exhibit with seals. Species displayed are native to the oceans around Denmark.
The Oceanarium is part of the Nordsøcentre, which also houses a conference centre.