Short on vacation days? These eight quick getaways to some of the world’s best dive destinations deliver all the thrills found during longer trips.

1. MALDIVES

One of the only scuba liveaboards with an onboard spa, the high-end, 129-foot M/V Four Seasons Explorer caters to 22 guests as it travels to the remote reefs of the Maldives, from Kuda Huraa resort to Landaa Giraavaru resort and back again, stopping at Male and Baa atolls. Each day sees just three dives, but it’s an itinerary that allows time for lolling on uninhabited white-sand beaches, plus waterskiing, wakeboarding and kayaking. When you do don a tank, you’ll see eagle rays, wrecks, and thick schools of fish such as rainbow runners, batfish, Moorish idols, and sweetlips. May to November, plankton blooms attract whale sharks and mantas, so sightings are likely. December to April, the water clears, offering visibility of 100 feet and greater.
fourseasons.com

2. DRY TORTUGAS NATIONAL PARK, FLORIDA

“Ninety percent of my people are return guests,” says Capt. Rick Pitts of those booking weekend trips May through December aboard his vessel, the 100-foot M/V Ultimate Getaway, bound for Dry Tortugas National Park, 67 miles south of Key West, Florida. The conditions and slight current make diving best suited for those with at least an intermediate ability, capable of six to eight dives a day. “It’s a trip for people who are already comfortable in their gear and ready for unrestricted reef access,” he says. The typical profiles follow 75- to 12-foot-deep ledges, plus pinnacles rising from 90 to 55 feet. “On the reefs, you’ll see pillar corals — those fuzzy-looking tall stalks that aren’t found in the Keys,” says Pitts. “Plus, goliath grouper everywhere and billfish swim right up to you, and we get the occasional whale shark.”
ultimategetaway.net

3. FLOWER GARDEN BANKS NMS, GULF OF MEXICO

“You get all the Caribbean fish, but you don’t need a passport,” says Sharon Cain of Flower Garden Banks National Marine Sanctuary in the Gulf of Mexico, about 100 miles off Freeport, Texas. Cain is owner of M/V Fling, a 28-passenger vessel running three-day trips February through October to the sanctuary’s coral reefs, formed atop three underwater mountains, West Bank, East Bank and Stetson Bank. All these sites, plus some oil rigs popular with divers, are famous for encounters with big stuff, from mantas and schooling hammerheads in spring to tuna and silky, bull and blacktip sharks year-round. The weekend trips depart Friday night and return Sunday before 6 p.m., and include seven dives. Fling also runs coral-spawning trips on the eighth day after August’s full moon; in 2015, August will see two, so two coral- spawning charters will witness the phenomenon — which is also prime time for whale sharks lured in by the spawn.
flingcharters.com

4. GREAT BARRIER REEF, AUSTRALIA

Mike Ball Dive Expeditions’ three-night Cod Hole and four-night Coral Sea fly-and-dive safaris deliver all the Great Barrier Reef’s highlights — schooling giant trevally, soft-coral gardens, bumphead parrotfish — while cutting down at-sea travel times. Divers booking the full seven-day tour spend 12 hours in transit to Cod Hole from the departure city of Cairns, Australia. Those on the shorter trips start or end their safari at midway point Lizard Island, so cut off some travel time with a flight to or from Lizard Island. Voyages include stops at Cod Hole, home of barrel-size grouper that easily warm to divers. On the three-night trip, guests also experience sites like Steve’s Bommie, a garden of plate corals swarmed by anthias and reef fish. The four-night, 14-dive itinerary moors at the site Amphitheater for a feed that attracts upwards of 20 gray and whitetip reef sharks. Plus, you’ll drift dive North Horn, home to more predators.
mikeball.com

5. GUADALUPE, MEXICO

You’ll likely be sleeping when the M/V Horizon clears Mexico customs, making this among the most painless treks to Baja. The flip side: You’ll log roughly 34 hours in transit, which is why the trips take five days. The reward is guaranteed encounters with 15-foot great whites, most of which belong to a community of 100-some identified regulars. “It’s thrilling,” says Terry Salmon, general manager for the charter company. “In the cage, you’re that close to an incredibly big and powerful animal that’s dangerous.” The company has been diving the area since 2001, offering trips from early August through mid-November. The boat accommodates 30 guests in two-person cabins, but takes only 16 passengers on these long-haul trips to afford the group more space. horizoncharters.com

6. CHANNEL ISLANDS, CALIFORNIA

In Southern California’s Channel Islands Marine Sanctuary — comprising five of the eight Channel Islands — diving kelp forests is not unlike hiking among redwoods — greenery towers overhead, sometimes as tall as 120 feet. This is just one of the highlights of the two-, three- and four-day liveaboard trips that target one of four general areas: the Northern Channel Islands of Anacapa, San Miguel, Santa Rosa and Santa Cruz; the Southern Channel Islands that include Catalina and Santa Barbara; inshore wrecks; and offshore sites such as Cortes Bank, the fleet’s most popular site with locals. Aside from kelp, the other prime attraction is the population of seals and sea lions. You’ll also dive with moray eels, bat rays, octopuses and 500-pound black sea bass. As for the three-vessel fleet, Truth carries 45 passengers, and Vision and Conception each carry 46, all in open-berth configurations. truthaquatics.com

7. KOMODO, INDONESIA

M/V Tatawa offers three- and five-day trips through Komodo National Park, home to mantas, frogfish, nudibranchs and, yes, those dragons. The ship’s itinerary depends on weather conditions, as well as the wishes of the eight passengers. The 80 or so dive sites — you’ll visit up to four a day — include places such as Manta Alley, where tidal changes between an offshore island and its pinnacles sweep in clouds of plankton, attracting trains of mantas. The Komodo stretch is also a macro wonderland where night dives yield encounters with oddities like seamoths, coconut octopuses, ghost pipefish, juvenile batfish and much more. divekomodo.com

8. SIMILAN ISLANDS, THAILAND

Catering to Thailand’s adventuresome backpacking crowds, PADI Five Star IDC Khao Lak Scuba Adventures operates six liveaboard vessels in the Andaman Sea, departing the coastal town of Khao Lak, north of Phuket. All gear, plus meals and snacks, is included. Each of the six vessels is configured differently; the M/V Manta Queen 6 takes 16 passengers; the Manta Queen 3, 31. Itineraries range from three to five nights inside Similan Islands National Park and include a combination of visits to Koh Bon and Koh Tachai. All trips conclude at current-swept Richelieu Rock, perhaps the country’s most famous dive site for possible encounters with mantas, whale sharks, and schooling barracuda, plus reef residents like octopuses and ghost pipefish. khaolakscubaadventures.com