Take the bus or tram... Little parking in the area... May get lucky if you go early...
Metered parking is available on neighboring streets and lots. The parking garage on Grinnell St has a tram that can carry you around town, including around the area where the Key West Aquarium is located. Be prepared to spend 35-50 dollars for a full day of parking, depending on how close you are to downtown! You might also want to purchase tickets to the Old Town Trolley tours, which runs all around the island at set times in a 'hop on, hop off' manner at set locations! Call the Key West Aquarium for more details on how to get on the trolley and ticket pricing.
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