Nadine,
This will be our second cruise to the Southern Caribbean. in November of 2008 we cruised out of San Juan and made stops at St. Thomas, St Lucia, Antigua, Dominica, Barbados and St. Kitts. All of the islands were beautiful.
When in St. Lucia I would highly recomend the Land and Sea combo to Soufriere excursion. We did this excursion and had a wonderful time even in the pouring rain. Your board a very comfortable coach bus and travel across the island stopping in a small fishing village and then on to the Soufriere Volcano where you can actually walk down into the mouth of the volcano. You reboard the bus and head down to a beautiful botanical garden for a short walking tour. You again board the bus and head down to the pier for a fun filled Catamaran ride past the majestic Pitons, to a quite cove for a brief swim before setting sail back to the Cruise ship.
My younger sister lived in St. Kitts for several years and she recommended we take the beach excursion which ended in Frigate Bay. There is a quaint little beach bar called Mr. X's Shiggity Shack. there was delicious food and fantastic drinks. It is a small beach area with lounge chairs and plenty of entertainment.
We have not yet been to St. Maartens so we will be looking for some new adventures when we dock there.
My wife and I have been on three cruises with Carnival and are looking forward to our fourth. We are from Philadelphia, Pennsylvania in the good ole USA