Chankanaab National Park & Punta Sur Ecological Reserve -- Chankanaab National Park is the pride of many islanders. In Mayan, Chankanaab means "little sea," which refers to a beautiful landlocked pool connected to the sea through an underground tunnel -- a sort of miniature ocean. There was some hurricane damage to this natural pool, but it was mostly surface wear. Snorkeling in this natural aquarium is not permitted, but the park has a lovely ocean beach for sunbathing and snorkeling. Arrive early to stake out a chair and palapa before the cruise-ship crowd arrives (9-10am). Likewise, the snorkeling is best before noon. There are bathrooms, lockers, a gift shop, several snack huts, a restaurant, and a palapa for renting snorkeling gear.
You can also swim with dolphins. Dolphin Discovery (tel. 800/293-9698; www.dolphindiscovery.com) has several programs for experiencing these sea creatures. These are popular, so plan ahead -- you should make reservations well in advance. The surest way is through the website -- make sure to pick the Cozumel location, as there are a couple of others on this coast. There are three different programs for swimming with dolphins. The one of longest duration costs $125 (£69) and features close interaction with the beautiful swimmers. There are also swim and snorkel programs for $75 and $99 (£41-£54) that get you in the water with these creatures.
Surrounding the landlocked pool is a botanical garden that did suffer greatly from the hurricane and will take some time to come back. Admission to the park is expensive, costing $16 (£8.80) for adults, $8 (£4.40) for children 9 to 12. I think the authorities are trying to recoup some of the money spent restoring the park, and it is being marketed to the cruise ship crowd. The park is open daily from 8am to 5pm. It's south of town, just past the Fiesta Americana Hotel. Taxis run constantly between the park, the hotels, and town ($10/£5.50 from town for up to four people).
Punta Sur Ecological Reserve (admission $10/£5.50) is a large area that encompasses the southern tip of the island, including the Columbia Lagoon. The only practical way of going there is to rent a car or scooter; there is no taxi stand, and, usually, few people. This is an ecological reserve, not a park, so don't expect much infrastructure. The reserve has an information center, several observation towers, and a snack bar. The observation towers were destroyed in the hurricane and were still not reconstructed on my last visit. The information center was struck hard, too. And many of the trees on this side of the island came down, while others completely lost their leaves. These, I am told, will make a comeback, but before you go all the way out to the park and pay admission, ask around about the condition of the vegetation -- it adds a good bit to a visit here. Punta Sur has some interesting snorkeling (bring your own gear), and lovely beaches that are kept as natural as possible. Regular hours are daily 9am to 5pm.