ZONA HOTELERA. Wanting to take a dive but feel too inexperienced to take the dip? If so, then head over to AquaWorld for diving classes and tours that cater to divers who have a wide range of experience. AquaWorld provides diving classes for those who want to stay in the pool or for the more adventurous who want the exhilaration of a confined-space or open-water dive. If you're less adventurous than your travel companions, then take a unique trip in a modified version of the glass-bottom boat that lets you stand in an underwater room and look out through windows.

Sharks have to constantly stay in motion to breath through their skins, according to scientists. But there's at least one place where these amazing creatures cool their wheels-the Cave of the Sleeping Sharks. The sharks use bubbles from underwater springs to breath, letting them relax for a while. There are not as many sharks nowadays because of heavy diver activity, but you can still catch one or two snoozing every once in while.

The coral reefs in the waters just off of the El Garrafón National Park Island are some of the most visited in the Mexican Caribbean. Located in shallow waters, the reefs provide an excellent opportunity for snorkeling and watching colorful fish. More experienced divers may opt for a dip along one of the largest reefs in the Caribbean, Manchones. For those who wish to stay above the waterline, glass-bottom boats make regular tours, and the island is a favorite nesting spot for many varieties of birds.

ZONA HOTELERA. Divers-to-be can avoid multiple-day courses for certification by signing up for a resort course at Scuba Cancún. Run by experienced diver Captain Luis Hurtado, Scuba Cancún enables beginners to start experiencing the underwater world after an informative, hands-on course of only four hours. With Captain Hurtado, exploring the submersed world of Caribbean is at your fingertips, even if you've never before strapped on flippers.