All around Isla Cozumel, the Caribbean Sea glitters a hundred shades of blue. Beneath the waves, Cozumel’s pristine coral reefs  make for spectacular diving  and snorkeling , the island’s number-one draw.
San Miguel de Cozumel—usually just called Cozumel, since it’s the only city on the island—is where the ferries from Playa del Carmen  land. It’s also where cruise ships, as many as 10 per day in the high season, arrive; it’s then that the waterfront promenade becomes a human river, flowing slowly down a channel of jewelry stores, souvenir shops, and open-air restaurants.
Just a few blocks from the promenade, another Cozumel emerges—a small, friendly community where old folks sit at their windows and dogs sleep in the streets. In spring, masses of orange framboyán (poinciana) flowers bloom on shade trees in the plaza, and festivals and religious celebrations are widely attended.
Cozumel’s interior—including an important Maya ruin —and its eastern shore are yet another world, lacking even power lines and telephone cables. Heavy surf makes much of the eastern shore too dangerous for swimming, but you easily can spend a day beachcombing or relaxing on the unmanicured beaches and lunching at small restaurants overlooking the sea.
As Mexico’s largest island, it shouldn’t be surprising to discover that it’s so multifaceted. But it’s hard not to marvel at how stark the differences are. Come for the diving and snorkeling, but leave time to experience a side of Cozumel you may not have expected.
By Air: Cozumel International Airport (CZM, tel. 987/872-2081, www.asur.com.mx ) is approximately three kilometers (2 miles) from downtown. The airport has an ATM in the departures area, AmEx currency exchange at arrivals, and a few magazine stands and duty-free shops. Private taxis from the airport run US$10–32, depending on the distance to your hotel, while shared taxis are US$4–10 per person, departing every 5–30 minutes. (You also can save money by booking round-trip service.)
By Bus: Although there are no long-distance buses on Cozumel (it is a pretty small island, after all), you can buy tickets for buses departing from Playa del Carmen  at Ticket Bus (main ferry pier, Av. Rafael Melgar, no phone, 7 a.m.–9:30 p.m. daily); there’s a second office at the corner of Calle 2 and Avenida 10 Sur (tel. 987/869-2553, 7 a.m.–9 p.m. daily). There is a US$0.75 surcharge for all tickets, but it’s a small price to pay for a guaranteed seat.
By Ferry: Ferries to Playa del Carmen (US$11.75 each way, 30 minutes) leave from the passenger ferry pier across from the central plaza. Two companies—UltraMar (Av. Rosado Salas at Av. 45, tel. 987/869-3223, www.granpuerto.com.mx ) and Mexico Waterjets (Calle 6 Norte btwn Avs. 20 and 25, tel. 987/872-1578, www.mexicowaterjets.com.mx )—operate the boats; the service and fares are identical, though UltraMar’s boats are somewhat newer. Between the two companies, at least one ferry leaves Cozumel every one to two hours on the hour from 6 a.m. to 9 p.m. daily.
Car ferries operated by Transcaribe (tel. 987/872-7688) depart from Cozumel’s international pier at 11 a.m., 4 p.m., and 10 p.m. Monday–Saturday and at 11 a.m. and 10 p.m. on Sunday. On the mainland, the ferries come and go from the Calica/Punta Venado dock south of Playa del Carmen at 8 a.m., 1:30 p.m., and 6 p.m. Monday–Saturday and at 8 a.m. and 6 p.m. on Sunday. The trip takes about 90 minutes and costs US$32 for a car including driver, and US$5 for each additional passenger. Arrive at least an hour in advance, each way, to get a spot.