Renee - you can walk around limited areas of Atlantis for free. IF you want to see the aquarium/dig- which i highly recommend it will cost about $25.00 per person. You enter Atlantis thru the casino, there will be a kiosk where you buy your tickets to the dig. There is a common area where you can view part of the aquarium, but you do miss out on a lot.
The beach at Atlantis is not free. You can purchase a day pass for use of the beach only- waterslides are not included.
St. Thomas - hit the beaches, do some snorkeling, do some shopping, walk to Paradise Point from the pier and take the tramway up the mountain for an amazing view of the harbor. check out this link- www.vinow.com - very helpful
St. Maarten - beach, snorkel, shop. Grab a cab and take an island tour with a beach stop. Golden Eagle Catamaran sail is a great excursion if you want to swim, snorkel and beach.
Check out what the cruise line is offering for shore excursions, some excursions you can only get thru the cruise line.
ReneeC: We visited Nassau last April. We planned to see the island on our own. There were 8 in our party. When we headed out of the terminal there are many locals there offering to take you on a tour. Well, with safety in numbers, we decided to do this. They charged us $20 per adult and $10 per child.
Gladstone was the mans name. He took us for a tour of the island, showing us the government buildings, schools, u.s. housing, the high rent district as well as the lower income housing. He gave a great history lesson of his home. The kids were very entertained by his stories, quizes and information.
Another thing he did was took us to some locals who have little shops/stands set up off the main strip. These folks were so friendly and really enjoyed the company (and it was a bonus if you bought something).
He also introduced us to a relative who was doing hair braiding right outside the terminal. Was a great experience and would recommend it to anyone visiting.
And yes, he did take us to Atlantis. We were able to see the inside part of the aquarium, the casino, the grounds (not the beach). We were gone for about 2 1/2 to 3 hours total.
Good luck and enjoy.
RCCL Freedom of the Seas 2/10
Carnival Legend 2/09
Carnival Victory 2/08
Carnival Liberty 7/07
Carnival Valor 4/06
Carnival Celebration 4/05
Carnival Sensation 4/04