For $15 you can hop on and off at various waterfront restaurants I think this starts at Panama Hatties or the Waterway and goes down south to West Palm Beach and then back.
Personally, I don't think it's worth it, but if you're a tourist and don't know the area well, this is perfect; you get a scenic tour that most residents don't have the chance to see and not have to worry about parking and/or getting lost.
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