National Aquarium Denmark, Den Blå Planet (Danish: Den Blå Planet, Danmarks Akvarium) is a public aquarium in Denmark. The original aquarium was located in Charlottenlund, but this facility closed in 2012 and most of the animal collection was relocated to the new and much larger aquarium Den Blå Planet (lit.: The Blue Planet) in Kastrup, a suburb of Copenhagen. The National Aquarium Denmark, Den Blå Planet opened to the public in March 2013 and is the largest aquarium in Northern Europe.