Our options of getting to South Beach from downtown Miami were the bus, taxi, or water taxi. I don't know why you would take the first two when you can take the water taxi! Round trip it was $20 for a 35 minute boat ride each way. It was really nice to see the Miami area on a boat and it doubled for us as a sightseeing drive as well as transport to the beach. I really enjoyed it and would definitely recommend it, especially if you don't plan on taking any other boat ride.
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