Snorkeling and Scuba Diving in Cozumel

Aldora Divers. Aldora Divers offers reef dives on fast boats and accommodations in Villa Aldora, a 12-bedroom inn just north of town. They also have trips to pristine dive sites and shipwrecks off the windward coast. Calle 5 Sur, between Av. Rafael Melgar and Av. 5, Cozumel, Quintana Roo, 77600. 987/872-3397; 210/569-1203 in U.S.

Aqua Safari. One of the island's oldest and most professional shops, Aqua Safari provides beginning and advanced PADI certification and daily introductory scuba courses. Owner Bill Horn has long been involved in efforts to protect the reefs and stays on top of local environmental issues. Av. Rafael E. Melgar 429, between Calles 5 and 7 Sur, Cozumel, Quintana Roo, 77600. 987/872-0101.

Aquatic Sports and Scuba Cozumel. Sergio Sandoval of Aquatic Sports and Scuba Cozumel gets rave reviews from his clients, many of them guests at the Flamingo Hotel. In addition to the usual excursions, he'll take you out for wreck dives, underwater photo safaris or to hunt invasive lionfish. Calle 21 Sur and Av. 20 Sur, Cozumel, Quintana Roo, 77600. 987/872-0640; 987/100-9033 mobile. www.scubacozumel.com.

Blue Angel. Blue Angel offers combo dive and snorkel trips so families who don't all scuba can still have fun together. Along with dive trips to local reefs, they offer PADI courses. Carretera Sur Km 2.2, Cozumel, Quintana Roo, 77600. 987/872-1631 or 866/779-9986.

Del Mar Aquatics. Del Mar Aquatics, in operation since 1987, offers dive trips, certification, and fishing trips. Casa Del Mar Hotel, Carretera Sur Km 4, Cozumel, Quintana Roo, 77600. 987/872-5949.

Eagle Ray Divers. Eagle Ray Divers offers snorkeling trips and dive instruction. (The three-reef snorkel trip lets nondivers explore beyond the shore.) As befits their name, the company keeps track of the eagle rays that appear off Cozumel from December to February and runs trips for advanced divers to walls where the rays congregate. Beginners can also see rays around some of the reefs. La Caleta Marina near the Presidente InterContinental hotel, Cozumel, Quintana Roo, 77600. 987/872-5735; 866/465-1616 in U.S. www.eagleraydivers.com.

Fury Catamarans. Fury Catamarans runs snorkeling tours from its 45-foot catamarans. Rates begin at about $59 per day and include equipment and a guide, soft drinks, beer, margaritas, and a beach party with lunch. Carretera Sur, Km 3.5, beside Casa del Mar Hotel, Cozumel, Quintana Roo, 77600. 987/872-5145.

Scuba Du. Dive magazines regularly rate Scuba Du among the best dive shops in the Caribbean. Along with the requisite Cozumel dives, the company offers night dives and an advanced trip to walls off Punta Sur. At the Presidente InterContinental hotel, Cozumel, Quintana Roo, 77600. 987/872-9505; 310/684-5556 from the U.S.