fonger, You will not need a taxi. You can walk the town in an hour. Plenty of shops, snacks, etc. In June there were alot of Bald Eagles with their young. It will be easy to kill six hours with minimal cost.
Carnival Celebration 2003
Carnival Elation 2005
Carnival Conquest 2007
Royal Caribbean Rhapsody of the Seas 2009
Carnival Freedom 2010