The Baltimore Aquarium is huge so absolutely plan on spending a few hours here and even then you might now see everything. The have every type of fish you can think of and even some you didn't know existed. You much purchase a ticket which will have a time that you can enter so it can be pricey for a family of four. The other bad thing is it gets very crowed (lots of schools in the area take field trips here). It is on a whole a very nice aquarium.
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