The Key West Aquarium is one of the Florida?s oldest aquariums built in 1932 to 1934. It opened in 1935 during the Great Depression period as part of the Works Progress Administration Program. In less than a year of opening, the aquarium was one of the structures in Key West damaged by the hurricane. It was then become an indoor rifle range for United States Navy and Marine Corps during World War II. Until 1960, the aquarium was renovated and reopened. The roof was added to prevent algae bloom in its exhibits.

There are five major exhibits in the Key West Aquarium. The Alligator Exhibit features one to three year old alligators from an alligator farm in Homestead, Florida. Once these alligators reached the age of four and above, they will be returned in the farm and will be replaced by younger alligators. On the other hand, the Atlantic Shore Exhibit features sea turtles, sharks, tropical fish, game fish, and a mangrove ecosystem. To mount this exhibit, 50,000 gallons of salt water was diverted in the lot to sustain a natural-like habitat or marine animals. There is also a Jelly Fish Exhibit which displays Moon Jelly Fish which is often spotted at Key West coasts.

Visitors can enjoy the tour in the Feed A Shark portion of the aquarium where they can feed sharks different kinds of sharks like nurse sharks, sandbar sharks, and bonnet head sharks. The tour also includes a face-to-face interaction with juvenile nurse shark in the nursery.

The Key West Aquarium also offers a view to the lower sea environment which can only be seen during snorkelling or diving. The Tank Touch houses some Echinoderm species as well as the unofficial mascot of Key West, the conch. Visitors can hold these creatures freely.