Underwater world is very cool. They have several tanks with different habitats in each one. If I recall correctly there is one for a reef enviornment, a deep sea environment, and a Minnesota Lake enviornment.
The location of the Aquarium has always thrown me off. It's in the basement of the Mall of America. I guess if you want something other than shopping and riding rides you can go to Underwater World and see the fish. I'd recommend it, it can be fun.
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