I took the Hop on Hop off Trolley in Key West but purchased our tickets before we left home. (Saved a lot of money since children under 12 were free and the fare was only $17.00 and not $29.99 if purchased via Carnival.) Very informative but we did not have time to actually visit all the stops.
And we had a beach day in Cozumel since I was just there in February while sailing with Celebrity.
I did a buch of research on the internet, but a great Taxi Driver did not take us to the beach we reserved - which was very rocky. He took us to another beach which we enjoyed and then shopping!
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