You can meet more than 20,000 aquatic animals from all over the world, displayed in 53 aquariums, at this Danish National Aquarium. The building itself is an architectural masterpiece, with a circular interior resembling currents, and is home to otters, jellyfish, flatfish, sharks and many other species of fish. You can wander through the water tunnel surrounded by glass, allowing you to see fish and marine life of all kinds from all angles. And do not miss the opportunity to feed the interesting piranha!