Kastrup, Denmark

The Blue Planet

Vortex-shaped aquarium hosts Europe's largest school of piranhas and other ocean creatures.

The striking architecture of the Blue Planet aquarium resembles a swirl of metal tentacles, and inside its gleaming structure are 20,000 fish and ocean creatures.

Opened in 2013, the Blue Planet replaced Denmark’s national aquarium, which itself opened in 1939. The old aquarium had the misfortune to open at the same time that World War II broke out so it was not a great time to be in the aquarium business, especially as they could no longer import fish. The hallways of the old aquarium also had awful ventilation, so that when it first opened people would pass out from the suffocating air. In 1944, a city strike caused the power to go out and staff used pedal power to pump oxygen into the tanks to keep the fish from an untimely demise.

As the museum outgrew its space and became desperately in need of repairs, the original building was closed in 2012. The futuristic Blue Planet features 3,000 of the animals that were in the old aquarium, along with 17,000 additional watery fauna, including hammerhead sharks, sea lions, and Europe’s largest school of piranhas. Ambient music accompanies walks down its hallways that have blue swaying lights to replicate the feeling of being underwater.