When you get off of the ship and walk past the shops directly at the port, you will find cheap taxi's that will take you wherever you want to go. We wanted to take an excursion to go to Magen's Bay but they all were only like 2 hours long which is not enough time to fully enjoy it. Taxi was about $16 (for 4 of us) and we were at Magen's Bay in about 15 minutes. Magen's Bay is everything as advertised. Beautiful beach and scenary and since we were the only ship in port, it was not very crowded. Great snorkeling on the far right of the beach along the rocks. Make sure you grab something to eat and drink at the Beach bar!
We took the public bus to Payne's Bay beach which was an experience. It was much cheaper than a taxi since it cost only $1!!!! Saved us a bunch of money and it was neat to ride through the city. Bus route takes you directly through a very rough section of Bridgetown. The beach is beautiful with plenty of room. Beach chairs and umbrellas were available for rent for cheap! I did some research before coming here and said that if you swim out to the catamaran's (decent swim), you will see all kinds of sea turtles. I didn't expect to see any but it was a great experience because they were all over. People from the cruise ship payed $75+ for the excursion and ours cost only $1 for the bus ride. Locals walk up and down the beach selling stuff or providing water activities. We went on the Jetski for a cheap price!
We took the Adrenaline Zipline Adventure excursion which was a blast. On TripAdvisor it is rated the #1 thing to do in St. Lucia. The ride to the rainforest was about 35-40 minutes and that was fun in itself. Riding up steep hills and seeing the scenery was amazing. The zipline were VERY safe as you are locked in and secured 3 different ways. There are about 18 platforms plus "2 surprises" along the way. As you end the tour you get a rum punch to cap off the day. There are great shops right outside of the cruise ship as well as some neat bars with cheap drinks.
Took a taxi to Cockleshell beach. Our taxi driver was great as she stopped and let us out at certain places to take pictures. This was a neat beach because it had black sand. There was an awesome bar & grille there called Reggae beach bar. There was also monkeys, pigs, and goats there as well to see. The beach had great views of St. Kitt's sister island "Nevi's". Lots of shops outside of the cruise ship but surprisingly not much to eat around there.
St Maarten was my favorite of all the ports on this cruise. We took the Golden Eagle Catamaran ride and snorkel to a private beach. We had so much fun snorkeling with thousands of fish right underneath our catamaran as soon as we anchored. The views on the beach are amazing and the water is crystal clear. Our group of people started jumping off the side of the catamaran and other people started to join in on the fun. Rum punch and sandwiches were provided. On the way back to the ship, the captain stopped in front of the famous Maho Beach runway as a plane was heading in to land. Wow was that plane low! Overall I absolutely recommend doing this excursion as we had a great time. After the excursion we took the water taxi downtown ($6 for all-day as many trips back and forth as you like) where there were great beachfront restaurants. Tons of shopping to do downtown and the people were very friendly.