Cozumel is 20 minutes by ferry from Playa del Carmen — making it one of the most convenient serious dive and snorkel destinations in the world. The island is 48 kilometers long, has some of the clearest water and most diverse reef systems in the Western Hemisphere, and deserves a full day even if you're not a diver or snorkeler.
Getting there — ferry logistics
Three ferry companies operate between Playa del Carmen's main dock and Cozumel: Ultramar, Barcos Caribe, and Mexico Waterjets. Departures approximately every 30 minutes from 6am to 10pm. One-way fare: $240–280 MXN depending on company. Journey time: 20–25 minutes. Buy tickets at the dock or in advance online (advance purchase saves queuing at peak times — particularly morning departures). The return schedule from Cozumel mirrors the Playa departure schedule. Last ferry back: approximately 10pm.
The reefs — what to expect
Palancar Reef: The most famous reef on Cozumel, accessible by boat tour from the island's main port area (San Miguel). Enormous coral formations, exceptional visibility (often 30+ meters), and a fish population that includes eagle rays, nurse sharks, sea turtles, and hundreds of reef fish species. Snorkel tours to Palancar: $40–60 USD including equipment. Dive tours: $70–100 USD for two tanks.
Colombia Reef: Less visited than Palancar, deeper, and considered by many dive instructors to be the superior reef. Massive coral pinnacles and wall diving down to 30+ meters. Better for experienced divers than snorkelers due to depth.
Chankanaab Park: The most accessible reef from shore on Cozumel — a marine park with shallow snorkeling, sea lion shows, and beach facilities. Entry: $29 USD. Snorkeling equipment included. This is the easiest entry point for first-time snorkelers who want to see tropical reef without a boat.
Beyond the reefs
San Miguel (Cozumel's main town) has a pleasant waterfront malecón and several excellent seafood restaurants. La Habichuela and El Moro are both well-regarded for local cooking at non-tourist prices ($150–300 MXN per person). The island's eastern coast is almost entirely undeveloped — wild beaches, wave-exposed, not suitable for swimming but worth driving for the scenery. Renting a scooter ($30–40 USD for the day) or a Jeep ($60–80 USD) from San Miguel gives you the flexibility to reach the eastern coast and the quieter southern tip.
Day trip logistics
Take the earliest ferry you can manage (7am departure from Playa). This gives you 10–11 hours on the island. Book your snorkel or dive tour in advance during peak season (December–March, July–August). The midday heat on Cozumel is significant — the reef is the most comfortable activity between 8am and noon. Save the town, food, and scooter exploration for the afternoon.