Half Moon Caye Natural Monument, Belize
Credit: Tobias Mueller-Prothmann / Getty Images

This classic tropical island – palm trees, white sand, blue water – is most famous as a stopping off point for trips to the Blue iconic Hole and its resident red-footed boobies. But thriving coral reefs right off the beach make it a snorkeler's paradise. The varied and abundant marine life includes staghorn and elkhorn coral, octopus, conch, parrotfish, yellowtail, tilefish, and many other small reef dwellers. Don't have all day? Hol Chan Marine Reserve, Shark-Sting Ray Alley and Mexico Rocks snorkel sites are just a few minutes from San Pedro. Day-long trips with Belize Dive Services include breakfast and lunch.