A very fast ride in a speed boat.

If you go to Key West, go to the end of Duval Street. There is a walkway at the end of the street that angles off to the left toward Mallory Square. The first thing you see will be some jet skis for rent, and next to those a speedboat named "Sea Rock-It." That's it in the top picure. It has two powerful engines for a claimed speed of 65 mph. Talk to the gentleman under the unbrella. He will sell you a 30 minute ride that shows you all of Key West with no time wasted. I don't think the ride is cheap, but he might haggle. We sat for a while listening to his pitch. It was very entertaining.