10 Secret Mexican Islands You Can Have All to Yourself

Isla Holbox

Unlike the madness of Cancun, Isla Holbox is a breath of fresh air on the Yucatan. With sandy beaches, blue water, unpaved roads and a low-key vibe, it's worth a visit in its own right—but make sure not to miss the whale sharks.

The world's largest fish gather around the island from June to September, and numerous tour operators run boats to see the sharks up close. The Mexican government enforces strict regulations to prevent harassment of the sharks, but with an approved guide you can get right in the water and snorkel with them in brilliant—and pleasantly warm—water.

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San Pedro Nolasco Island

An easy day trip from the town of San Carlos, Sonora, San Pedro Nolasco Island (a.k.a. Seal Island) has some of the largest seal colonies in northwest Mexico's Sea of Cortez. It's a great place to dive: The inshore kelp beds are a veritable open-water aquarium, and hammerhead sharks and gray whales frequent the water further out.

It's also possible to visit the wreck of a U.S. Navy submarine that ran aground in 1920, was towed off the rocks, and sank. Trips to the island can be booked with dive shops and charter boat operators in San Carlos—a pretty, if slightly gringo-fied town—dominated by a rocky outcrop called Tetakawi, just a four-hour drive from the U.S. border in Arizona.

El Arrecife Alacranes

On El Arrecife Alacranes ("Scorpion Reef"), some 80 miles off the northern tip of the Yucatan Peninsula, you definitely won't have to deal with the hoi polloi. The reef is famed among fly fishermen as a hotspot for bonefish, the feisty speedster of the saltwater sandflats. But Alacranes is also just a great place to just go get away from it all, and to snorkel or dive, if you're in the mood.

Isla Perez, the largest of the five islands that make up the reef, is home to the reef's only inhabitants: a small contingent of Mexican marines and a lighthouse keeper who unofficially doubles as the mayor. There's no scheduled boat service, so you'll have to charter your own (usually from Progreso), bring your own food and water, and be prepared to sleep either on the boat or in a hammock under a simple palapa. Think of it as car camping, but with a boat—and your very own island.

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Isla de Mezcala

A quick boat ride from the largely indigenous town of Mezcala on Lake Chapala, near Guadalajara, Isla de Mezcala was a religious site in pre-Hispanic times. Its real claim to fame came in the early 1800s, during the Mexican War of Independence, when a group of rebels holed up on the island for four years, valiantly fighting off Spanish soldiers until the rebels were gripped by a typhoid outbreak and were forced to surrender. The doughty fighters' rough-hewn stone fort remains relatively well-preserved, and makes for a great place to spend a few hours exploring.

Chinchorro Atoll

Far down the coast of Quintana Roo, almost near the border with Belize, Chinchorro Atoll is a biosphere reserve replete with healthy coral reefs, tropical fish and sharks, the wrecks of two galleons, and an inner lagoon that's home to manatees and crocodiles. Roughly 35 miles offshore, and with more than 600 square miles of reef, Chinchorro is a little-known wonderland for snorkelers and for divers.

Most people visit the atoll as a reasonably-priced day trip from the tiny village of Xcalak, but you can also stay on the atoll overnight in a palafito, a fisherman's stilt house perched over the water.

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Isla Espiritu Santo

Off Baja California's east coast, Isla Espiritu Santo looks like a wicked bony spine rising out of the Sea of Cortes. The island has a spare otherworldly vibe, and its sea kayaking possibilities are the stuff of legends. The waters off Espiritu Santo often see turtles, rays, dolphins, sharks, and whales.

There's no shortage of opportunities to beach your kayak and explore the island's wilds on foot; or to don mask, snorkel, and fins and ogle the local marine life. It's easy to arrange a one-day or multi-day trip in La Paz, from which you can either paddle out to the island yourself or hitch a ride on a boat.

Guadalupe Island

The craggy remnant of two overlapping volcanoes, Guadalupe Island lies beyond the edge of the Continental Shelf, some 150 miles off the coast of Baja California. It's reachable only by doing a trip on a "live-aboard" dive boat, but it's sure to be the trip of a lifetime. During the 18th and 19th centuries, the island's populations of seals drew Russian and American seal hunters. Today, the majority of the people who live there are lobster and abalone fishermen.

But the star attraction is Great White Sharks, which congregate in the waters around the island from July through November. Several operators run multi-day excursions to the island that give guests the chance to get up close and personal in tough metal shark cages. Because several of the cages remain at the surface of the water, you don't have to be SCUBA-certified to go eyeball-to-eyeball with a Great White—you just need to be brave.

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Isla Isabel

Three hours by boat from San Blas, Nayarit, Isla Isabel is frequently called Mexico's Galapagos. The volcanic island, which is home to mangroves and surrounded by coral reefs, is protected as a national park—for good reason. It's a birder's paradise filled with awesome species like red-billed tropicbirds, magnificent frigatebirds, and blue-footed boobies. The island has a pair of beaches, turquoise water, and good spots for snorkeling and diving. It's possible to spend the night on the island, though you'll need to pack your own food and camping equipment.

The Marietas Islands

Hidden Beach, on one of the Marietas Islands, is a beach-fringed tidal pool that's completely enclosed within a rocky amphitheater. Roughly an hour's boat ride from the Puerto Vallarta area, the beach is accessible only by swimming in at low tide, and has the feeling of a Bond villain's lair—or a romantic hideaway. Be warned that you're not likely to have the place to yourself: It's been growing in popularity, and its limited accessibility means that boats sometimes stack up off the island to take advantage of low tide. But it's worth the crowds for your chance to sink your toes in the sand of a beach within an island.

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Bermeja Island

For centuries, Bermeja Island was marked on maps and nautical charts at a spot off the Yucatan Peninsula. But in 1997, in the midst of treaty negotiations with the U.S. over the demarcation of the shared maritime border in the Gulf of Mexico, the Mexican government sent a survey ship out to check on the island—and found nada. Despite numerous searches, no one has seen the island since.

Bermeja may have vanished, but its disappearance has given birth to some conspiracy theories, including one which holds that the CIA bombed the island back into the sea to frustrate Mexican oil claims in the Gulf. Those of a less paranoid bent of mind surmise that the island was wiped out by an earthquake, succumbed to sea-level rise—or simply never existed in the first place. Consider this the ultimate island-travel challenge: If you can make it to Bermeja, you can probably make it anywhere.

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Matt Jenkins recently spent two years living in Ciudad Juarez, Mexico. A former editor at Nature Conservancy magazine and the High Country News, he has also written for The New York Times, Smithsonian magazine, Men's Journal, and Saveur.