My two cents. St. Thomas is great for snorkeling. Either a catamaran sail/snorkel or take a ferry to St. John then a cab to Trunk Bay. Trunk bay is a beautiful beach with a self-guided snorkel. The water is crystal clear and warm. There are fresh water showers, lockers, a snack bar, and a couple of shops (not cheap-shop in St. Thomas). St. Thomas is a good place for buying jewelry. St. Maarten is a great place for shopping. The snorkeling isn't bad. You can also do a really fun sail on the America cup sailing yachts. You actually get to be part of the crew--it's a blast. Enjoy your cruise!!
St Martin is great for shopping!!!!!! The Castaway Girl Catamaran Snorkel is fantastic in ST. Thomas, as well as the parasailing!!!! We booked both through RCCL.
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Aventura Spa Palace-04/25/04
Rccl Explorer of Seas-04/17/05
Carnival Miracle-05/07/06
Carnival Victory-04/18/10
It's been about two years since St Thomas. We did a private beach excursion. Just a beautiful beach, blue, clear water, white soft sand, just lovely. You must get to a beach or in the water somehow in St Thomas and St Martin. We did go to the beach in St Martin but I believe it was on the French side. Was a very long ride and did not leave us with much time and it was very windy. There is a cute little beach right off the pier in St Martin. Shoud have done that.