There are several institutions known as the National Aquarium:

Africa National Marine Aquarium of Namibia

Asia National Museum of Marine Biology and Aquarium, Taiwan

Europe National Aquarium Denmark National Marine Aquarium, Plymouth, England

North America National Aquarium (Baltimore), U.S. National Aquarium (Washington, D.C.), U.S.

Oceania National Aquarium of New Zealand National Zoo & Aquarium, Canberra, Australia