Cozumel’s main tourism attraction has long been its proximity to the Great Maya Reef, the world's second-longest barrier reef.  Diving and snorkeling are both excellent from the shore or by boat. For island tours, ruins tours on and off the island, evening cruises, and other activities, go to a travel agency such as Proviajes, Calle 2 Norte 365, between avenidas 15 and 20 (www.proviajescozumel.com; tel. 987/869-0516). Office hours are Monday through Saturday from 9am to 5pm, Saturday from 10am to 3pm.

Scuba Diving

Cozumel is the number-one dive destination in the Western Hemisphere. Don't forget your dive card and dive log. Dive shops will rent you scuba gear but won't take you out on a boat until you show some documentation. If you have a medical condition, bring a letter signed by a doctor stating that you've been cleared to dive. A two-tank dive trip costs about $70 to $90; some shops offer an additional one-tank dive for a modest additional fee. A lot of divers save some money by buying a dive package with a hotel. These usually include two dives a day.

Diving in Cozumel is drift diving, which can be a little disconcerting for novices. The current that sweeps along Cozumel's reefs, pulling nutrients into them and making them as large as they are, also dictates how you dive here. The problem is that it pulls at different speeds at different depths and in different places. When it's pulling strong, it can quickly scatter a dive group.Generally, however, the current makes for an effortless diving experience if you just relax and let the scenery drift by. Photographers must adapt to the current and resist grabbing the coral in order to stop to take a photo—killing the coral in the process.

The role of the dive master becomes more important, especially with choosing the dive location. Cozumel has a lot of dive locations. To mention but a few: the famous Palancar Reef, with its caves and canyons, plentiful fish, and sea coral; the monstrous Santa Rosa Wall, famous for its depth, sea life, coral, and sponges; the San Francisco Reef, with a shallower drop-off wall and fascinating sea life; and the Yucab Reef, with its beautiful coral.

Finding a dive shop in town is even easier than finding a jewelry store. Cozumel has more than 50 dive operators, including: Aqua Safari, which has a location on Av. Rafael Melgar 429 at Calle 5 (tel. 987/872-0101; www.aquasafari.com). Dive Paradise (tel. 987/872-1007; www.diveparadise.com), next to the Naval Base at 602 R.E. Melgar, has been in business over 25 years and offers dive training at all levels. Liquid Blue Divers (tel. 987/869-2812; www.liquidbluedivers.com) arranges tours by appointment and provides high-quality service to small groups. Scuba Du (tel. 987/872-9505; www.scubadu.com), based at the Presidente InterContinental resort, offers excellent diving excursions, refresher courses, and all levels of diving certification.

Warning: Cozumel has many excellent dive shops (like the ones mentioned above) with experienced divemasters and high-quality gear. But, as in all popular dive destinations, some run “cattle boats,” packing way too may divers on a boat and supplying sub-par gear. It pays to do a bit of research, checking out websites and recommendations. Try to stop by the shop before signing up for trips and check out the gear and boats. Most of my Cozumel dives have been fabulous, but I have been on unfortunate outings, made more disappointing by my experience with the island’s excellent shops.

Cenote Diving on the Mainland -- A popular activity in the Yucatán is cave diving. The peninsula's underground cenotes (seh-noh-tehs) -- sinkholes or wellsprings -- lead to a vast system of underground caverns. The gently flowing water is so clear that divers seem to float on air through caves complete with stalactites and stalagmites. If you want to try this but didn't plan a trip to the mainland, contact Germán Yañez (www.germanyanez.com; tel. 987/113-7044), based at 60 Avenida 117, between Calles 2 and 4 North. He offers all-day cenote tours as well as cave dive training. The cenotes lie 30 to 45 minutes from Playa del Carmen, and a dive in each cenote lasts around 45 minutes. Dives happen within the daylight zone, about 40m (131 ft.) into the caverns, and no more than 18m (59 ft.) deep. Open water certification and at least five logged dives are required. For those without diving certifications, a cenote snorkeling tour is also offered.

Snorkeling

Most resorts offer snorkeling equipment, and many dive shops do, as well. Even though you won't see a lot of the more delicate structures, such as fan coral, you will still see plenty of sea creatures and enjoy the clear, calm water of Cozumel's protected west side. When contracting for a snorkel tour, stay away from the companies that cater to the cruise ships. Those tours are crowded and not very fun.

Boat Trips

Travel agencies and hotels can arrange boat trips, a popular pastime on Cozumel. Choose from evening cruises, cocktail cruises, glass-bottom boat cruises, and other options. A real submarine tour is offered by Atlantis Submarines (tel. 987/872-5671; www.atlantisadventures.com). The tour includes 40 minutes at up to 30m (100 ft.) beneath the surface of the Chankanaab protected marine park (total excursion time is 1 1/2 hours). It costs $105 per adult, $65 for kids ages 4 to 12. Children under 4 are not permitted to take the tour.

Fishing

The best months for fishing are March through June, when the catch includes blue and white marlin, sailfish, tarpon, and swordfish. The least expensive option would be to contact a boat owner directly. A reliable operator offering deep-sea fishing and bonefishing in Cozumel is  Tres Hermanos (www.cozumelfishing.com; tel. 987/107-0655). The cost for an 8-hour excursion is $450 for up to eight anglers. Half-day trips are also available. Another option is to try the website GetMyBoat.com, which lists competitive pricing from a number of operators.

Beaches

Along both the west and east sides of the island you'll see signs advertising beach clubs. A "beach club" in Cozumel can mean just a palapa hut that's open to the public and serves soft drinks, beer, and fried fish. It can also mean a recreational beach with the full gamut of offerings, from banana boats to parasailing. They also usually have locker rooms, a pool, and food. The biggest of these is Mr. Sancho's (tel. 987/112-1933; www.mrsanchos.com), south of downtown San Miguel at Km 15 on the main road between the Reef Club and Allegro Resort. It offers a restaurant, bar, massage service, and motorized and nonmotorized watersports. Quieter versions of beach clubs are Playa San Francisco (no phone) and Paradise Beach (www.paradise-beach-cozumel.com), next to Playa San Francisco. All of these beaches are south of Chankanaab Park and easily visible from the road. Several have swimming pools with beach furniture, a restaurant, and snorkel rental. They cost about $12 to enter. If you’re driving the coast looking for a club, stay away from those with large tour buses parked at the entrance—they’re sure to be packed with day-trippers from the cruise ships.

Once you get to the end of the island, the beach clubs become simple places where you can eat, drink, and lay out on the beach. Paradise Cafe is on the southern tip of the island across from Punta Sur Nature Park, and as you go up the eastern side of the island you pass Playa Bonita, Chen Río, and Punta Morena. Except on Sunday, when the locals head for the beaches, these places are practically deserted. Most of the east coast is unsafe for swimming because of the surf. The beaches tend to be small and occupy gaps in the rocky coast.

Golf

Cozumel has an 18-hole course designed by Jack Nicklaus. It's at the Cozumel Country Club (tel. 987/872-9570; www.cozumelcountryclub.com.mx), north of San Miguel. Greens fees are $134 for a morning tee time, including cart rental and tax. Afternoon tee times cost $89. Tee times can be reserved 3 days in advance. A few hotels have special memberships with discounts for guests and advance tee times; guests at Playa Azul Golf and Beach Club pay no greens fees, but the cart costs $25.

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.