When you dream about a Caribbean cruise, chances are you picture your toes in the sand and the cool surf lapping at your legs as the sun beats down. If that's your dream, then a beach day is a must while cruising in the islands. While many lines offer their own organized shore days, you can upgrade your shore excursion with a trip to one of these resorts. There, you can set up on the (sometimes private) stretches of sand and take advantage of the pools and water parks, plus activities like snorkeling, kayaking, and even horse back riding. You'll also find facilities like showers and bathrooms as well as spas that offer treatments you may not be able to book onboard.