Dive in Little Cayman, the Cayman Islands
If you want to enjoy one of the Caribbean's best dive environs without fighting spring break crowds or a big-resort atmosphere, bypass Grand Cayman for its littlest sister. The pace is soothingly lethargic, the beaches soft and mellow, the locals friendly (though scarce), and the diving sublime, especially off of Bloody Bay Wall, one of the world's best wall dives. When you aren't diving or lounging in a hammock, grab a bicycle, pedal the handful of roads that loop around the island, and visit the resident iguanas, some of who are measured in feet, not inches. This is about as away-from-it-all as you can get without a tent.

Conga Line Party, Barbados
This island has personality all year long, but really kicks it up in March and April with what's often tagged as the longest conga line—and the largest street party—in the world. The St. Lawrence Gap Entertainment district comes alive with live bands as "De Human Congaline" packed with festive, brightly clad partiers wends from Bridgetown to the Gap. The revelry continues each night at the Dover playing field.

Francisque Island, Islas Los Roques, Venezuela
This sublime bean-shaped cluster of islets off Venezuela's north coast rings some of the most beautiful water on the planet—no exaggeration—with more aquatic areas ripe for exploration than you could cover in a week. March is the best of all worlds here: It's big with windsurfers early in the month, then the gusts subside enough to excite the bone fishing enthusiasts. Meanwhile, scuba divers and beach lovers of all stripes roam around these protected islands with mouths agape, wondering if the scenery, weather, and evening caipirhinas at the posadas (guest houses) on Grand Roque are real or illusory.

Little Dix Bay in Virgin Gorda
So, you like to party but don't want to give up surreal Caribbean setting to sip an umbrella-flagged cocktail with the younger set? Head down to Little Dix Bay, where you can cloister yourself in the luxurious resort and head out to look for action at your whim. At Little Dix, you get a cover-shot crescent of sand caressed by soothing clear water and cradled by a luxury resort, with rooms and guest houses nestled into the natural environs. Oh, and there's a teeming reef just offshore. Oh, and a baker's dozen of other private beaches a short water taxi ride away. Oh, and the spa…
(www.littledixbay.com; 284.495.5555)

Eleuthera and Harbour Island, Bahamas
As spring begins to wash over the Bahamas, the Out Islands reveal themselves as the sparkle of this low-cut island chain, and these two ribbon-thin strips of sand shimmer like few others. Stretching about 90 miles long, Eleuthera is a mere half-mile to two miles wide, helping explain why its name derives from the Greek for "freedom." It's all about the beach here. And the azure waters, where divers can zip along on a fast drift with the blazing currents. Not to be outdone, Harbour Island basks in its own accolade, having earned the Travel Channel's World's Best Beach designation in 2005.

The Rolex Regatta in Saint Thomas, U.S. Virgin Islands
Oft overlooked by adventurers seeking less-traveled sands, Saint Thomas still holds charm, vibrant culture, and natural wonders. And every March the main U.S. Virgin Island hosts the three-day International Rolex Regatta, a popular event among the more-serious sailing set. Non-participants can tour the picturesque beaches of Magens Bay, snorkel Coki Point, or explore the lush hills that dominate the interior.

Pinney's Beach, Nevis
Alright, admit it, you don't know any more about cricket than you do about the history of Nevis, but that's okay. With five Caribbean World Cup cricket matches scattered throughout the month you've got plenty of time to study up before heading down. Or not; your other options include lounging on the soft, sugar-white sands of Piney Beach, which is accented by a handful of coconut palms and a cover-shot tropical lagoon in the shadow of Mount Nevis.

Villa Montana, Puerto Rico
Once you see this beach—three miles of dreamy, foliage-fringed, barely peopled sand, and 50 plantation-style villas—you won't care what month it is. Set on the pastoral northwest side of the island, this resort exudes the charm of the confidently private. But you won't be too alone: March is the tail end of the annual humpback whale migration, as the giant mammals loll through the Mona Passage. Viewing opportunities abound, from shore, boat and, for divers, smack amid the traveling cetaceans in the water.
(www.villamontana.com; 888.519.2888)

Pearl Resort, Moorea Island, French Polynesia
A visit here isn’t so much about the beach itself. The sand along Moorea’s north is nice enough but you might never even notice it because from the moment you set foot, flipper, board, or hull here you’ll be captivated by the water. The teeming reef sheltering the coast and the South Pacific fantasy views of Cook’s Bay and Opunohu Bay further west will lure any landlubber away from her towel.

Honda Bay, Palawan, Philippines
Serious scuba divers have probably heard of Honda Bay. The rest of you, listen up: The sand here is a stark white, and the fringing jungle a verdant green. Thatch huts line part of the shore and a pod of islets hovers offshore. The reef and its gazillion multi-colored denizens guard the bay, and if you want even more variety book a dive in the Tubbataha Reef Marine Park, a World Heritage site. Best time to visit is December through May.