The Sea of Cortez is the star in Loreto, and the five islands just offshore make for some of the best kayaking, sailing, diving, and fishing in North America. Paddling alongside jagged mountains and crystal bays, diving with mantas and giant squid, and pulling in mega marlin are all in a day's fun. Freediving, or breath-hold diving as opposed to diving with tanks, is becoming more popular as well. Loreto is the nearest major airport and city to Bahía de Magdalena (Magdalena Bay), the southernmost of the major gray whale calving lagoons on the Pacific coast of Baja, and Loreto was their stage in winter 2007 during the filming of a documentary called Whales.

Sea Kayaking -- Kayaking season is October through December and May through June, and although Loreto attracts mostly expert kayakers, options are available for novice recreational paddlers as well. Tour Baja offers Paddling South multiday trips ($1,045-$1,195) in one- or two-person fiberglass sea kayaks. Puerto Escondido is also an ideal starting point for experienced kayakers who want to reach Isla Montserrat; call Tour Baja for details. Land & Sea Eco Adventures offers kayaking day trips to Coronado ($90) and Danzantes ($115). Sea Trek Kayak (tel. 415/332-8494 in the U.S.; www.seatrekkayak.com), out of Sausalito, California, has been running weeklong island-hopping kayak camping trips here for 25 years; $995 per person includes all food, lodging, guides, fees, and gear.

Snorkeling & Diving -- Several companies offer snorkeling; most island exploration trips include snorkeling, and trips to Isla del Carmen, Isla Coronado, Isla Monserrate, and Isla Catalina all include snorkeling opportunities. The going rate is $65 including gear, snacks, and tips. Some fishing trips carry snorkeling gear on board to give anglers a chance to check out the underwater world.

For scuba diving, contact Dolphin Dive Center. It offers several diving sites where you can admire the underwater bounty of the Sea of Cortez. The two-tank trips cost $99 to $120 per diver, and a PADI dive master guides all tours. Snacks, Loreto Bay Marine Park fees, weights, two tanks, and a boat are included, but any equipment needed comes at an extra charge (air costs $5/tank, wet suit $10, BC [buoyancy compensator] $10, regulator with dive computer $12, mask/fins/snorkel $10). If you're new to scuba and would like to get certified, or if you want an advanced certification, Dolphin Dive Center also offers several PADI resort courses, which range from $150 for a daylong resort course to $650 for dive-master certification.

For something more unusual and boldly adventurous, take advantage of the run of giant Humboldt squid that pass inshore to spawn between Isla del Carmen and Isla Danzante from May through October. Dolphin arranges nighttime encounters with these ink-squirting apex predators, which can grow up to 90 kilograms (200 lb.) and travel in packs called shoals, with divers protected in shark-proof cages, for $200, with a minimum of three divers.

Sea Turtle Monitoring -- The Sea of Cortez is an important habitat for endangered sea turtles, but scientists still don't know how far they travel from these shores. Tour Baja and Baja By Kayak (tel. 613/135-1887; www.bajabykayak.com) are contributing to sea turtle research by capturing, measuring, and tagging sea turtles near Danzante and Coronado islands, and for $125, you can help. The classic trip is a camping overnight, and you can expect a short night, as nets are checked every hour, and when turtles arrive, the action begins. Tour Baja also offers daytime turtle trips.

Sportfishing -- The fishing near Loreto is exceptional, with a different game fish for every season. Winter and spring months are great for yellowtail, sea bass, roosterfish, and grouper; and summer is the time for big marlin, sailfish, tuna, and dorado. This is a protected marine park, and the catch is limited to fin fish, not more than 10 per day and five per species; marlin, shark, swordfish, and sailfish count as five, with only one allowed, and dorado, roosterfish, shad, and tarpon count as five, with only two allowed. Catch-and-release fishing is unlimited, and strongly encouraged. Baja Big Fish is the go-to operator for sustainable fishing practices; they offer fly-fishing as well.

The least expensive way to enjoy deep-sea fishing is to pair up with another angler and charter a panga from the Loreto Sportfishing Cooperative at the main pier in Loreto. Prices range from $150 to $180 per boat, depending on the size and availability of shade. You can also arrange your trip in advance through most resorts and tour operators or contact the fleets directly. People with their own boats can launch at the ramp just north of the malecón in town or at Puerto Loreto, 26km (16 miles) south of town; you'll need a fishing license from the marine park office at the marina, 136 pesos daily and 258 pesos a week. If you plan on running out to Isla del Carmen, it's better to launch from Puerto Loreto, which cuts 10km (6 miles) off the crossing. For tackle, head to Deportes Blazer (tel. 613/135-0911) on Hidalgo, the catchall sporting-goods store in town.

Whale Watching -- Loreto is the nearest major airport and town to Bahía Magdalena (Magdalena Bay), the southernmost of the major gray whale calving lagoons on the Pacific coast. For more information on popular whale-watching spots and tour operators elsewhere than Loreto, see the "Whale-Watching in Baja: A Primer" section later in this chapter. All hotels and tour operators can arrange (long) day trips to Magdalena Bay, for between $70 and $150, depending on whether lunch and an English-speaking guide are included. It's a 2-hour car or van ride each way, with about 2 hours on the water and lunch in between. To visit the whales at San Ignacio Lagoon, plan an overnight. Baja By Kayak has 2-night trips from Loreto for $995 to $1,150.

While the gray whales are Baja's number one attraction between January and March, they're not the only giant marine mammals in town. Right in Loreto Bay are large populations of migrating blue whales -- the largest animal in the world -- humpback, pilot, and sperm whales, local finback whales, orcas, and dolphins. They won't come up and commune with boat passengers the way the gray whales do, but it's still an awe-inspiring nature experience, without the commute. Land & Sea Eco Adventures runs daylong excursions into the bay for $130, while Dolphin Dive Center charges $150, including a naturalist guide and lunch on an island beach.

Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.