Half day snorkeling - View Belize's famous underwater world at world-class snorkel sites. Hol-Chan Marine Reserve is exploding with life; Shark-Ray Alley is a shallow sandy area that lets the snorkeler get up-close-and-personal with southern stingrays and nurse sharks. North of town, Mexico Rocks is 12 feet deep with giant brain corals that house shrimp, crab, and colorful Caribbean fish.