My wife and I went on a 5 day carnival cruise. The highlights were getting off the ship on Nassau, Half Moon Cay, and I can't recall the third island. But even then it was only about 4 hours per island.
I was incredibly bored 95% of the time. I had more fun driving from SC to Florida.
1967 Pontiac Firebird W/ 400 1967 Chevrolet C-10 1999 Chevrolet S-10 2000 Chevrolet Silverado Z71 2011 Mustang V6
