There are many cruises out of Tampa that go to the Cayman Islands. Three cruise lines offer the trips. See the schedule of departures below.
Grand Cayman Island is the cruise port and largest of the three Cayman Islands. It is located south of Cuba and west of Jamaica in the Caribbean Sea.
The Cayman Islands are one of the world's best diving destinations. Famous Seven Mile Beach is on the west side of the island. The town of George Town on Grand Cayman is the home of the National Museum, historic Fort George, and luxury shopping. The National Trust's Mastic trail winds through forest with native plants and animals.
Here is a short video about the world class diving available in the Caymans.