I really enjoyed St. Thomas, we booked the downtown shopping and Magen's Bay excursion which gave us 2 hours of shopping downtown and then 2 hours at the beach.  After you finish shopping you have about a half hour to take your purchases back onto the ship.  The tour driver also takes you to a couple of photo opportunities between the shopping and the beach.    
I think that next time I'm in St. Thomas I'd prefer more shopping time as you can get some amazing deals, especially on jewelry.    
We were a little late getting into port, our excursion was supposed to leave at 9:15 but I don't think they had started letting anyone off the boat at that time.  We ended up being let off with the crew as some other ladies in our elevator felt faint due to the crush of people on the floor above.  

St. Thomas

San Juan is a beautiful city and I would very much like to go back and spend some more time exploring.  We went on the Canopy zip line tour which was amazing and a lot of fun.  However, be warned that before you start the zip line adventure you have a 10-15 minute hike uphill.  They are in the process of putting in a gondola but I'm not sure when it will be finished.  All of the staff were very nice with the exception of one who was rather rude about halfway through the course.  Due to my height (or lack thereof) I had trouble with the braking and I found he was very rude and scolded me for not braking.  he also scolded my mother for not braking soon enough when he never told her to brake.  We had previously been told that the staff would call out to us when to start braking.  Other than that, everyone was very professional and pleasant.    
The bus driver taking us back to the ship was open to dropping some of us off at different areas of the city if we wanted so my Mom and I got off downtown to do some shopping before walking back to the pier.  If you like really nice tablecloths and other linens I'd suggest checking out The Linen House.  If you like colour changing clothing and accessories definitely check out Del Sol (there is one in St. Thomas as well).  

San Juan

I had to give Grand Turk a lower rating mainly due to the prices once you were on shore.  I'd definitely suggest booking an excursion as there really isn't anything to do other than check out the shops, Margarita-ville or hang out on the beach.    
We did the catamaran sail and snorkel and had a lot of fun.  Our tour was the last of the day and unfortunately we got a bit of a late start as the previous tour was a bit late in getting back.  We had been on a snorkeling excursion before in the Dominican Republic but I must say that the captain of this boat explained the best way of getting a good seal on the snorkel mask much much better which made the trip a lot more fun.      
Don't wait to buy your souvenirs for this stop - everything was much more expensive ($30 T Shirts and towels etc.)    
We didn't spend any time at the beach, however the ladies who shared our dining room table with us did and they let us know that if there is a ship leaving port while you are at the beach they make everyone get out of the water while it is preparing to leave and you can't get back in until the ship is safely away.    
The reason for this is that the cruise ships actually get very close to the island.  The water is about 26 feet deep around the island then it suddenly drops to 7000ft (according to the catamaran tour anyway).  This makes for some cool shots of the ships from the pier and the shore.  

Grand Turk

This is a great location for access to Emile's restaurant and the aft pool, water-slide area.  It's also mid-ship so there really wasn't that much movement.  However, the balcony is underneath the Emile's restaurant overhang so you won't be able to sunbathe out there.  We didn't find it very noisy with the exception of the deck party that was had mid way through the cruise.  They had the whole ship separated into teams (red, white and blue) and at one point they had each team stomping and making noise which make the cabin very loud.  We're both night owls though so it didn't bother us at all.

There is only one way through the barrier reef
surrounding the island so that means only one tender can come in and go
out at a time which also slows the process down a bit.I ordered a pop once and waited almost 20 minutes for it one day while I watched the server go back and forth from another lady 3 times bringing her what looked like an alcoholic beverage before I received mine.

Carnival Liberty Review

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