We did it on our own with our trusty Lonely Planet Guide. There are taxis at the pier at St. P. Getting back isn't that easy, the cabbie will drop you off at the pier gate and ANOTHER cabbie will take you to the ship. After a long day, the $5 to get back to the ship is a bargain.
It is a wonderful, but VERY WEARING, itinerary. From conversations we had with others, we saw about 4X as much as the people on ShoreX's.
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pamda -- Cruise Mates Utility Infielder