During our 1-week stay at El Presidente (see review of El Presidente), we explored the island a bit. (See separate short review of Chankanaab.) We rented a jeep on our first day, and drove around the island. The various ruins are nothing spectacular compared to what you'll find on the mainland, but are interesting nonetheless. San Gervase (sp?), on the road that bisects the island, is the best of the bunch.
The island road goes along the shore on the south end of the island. The north end is inaccessable by anything other than heavy-duty four-wheel-drive vehicles or ATVs. DON'T try it in a rental jeep.
The beaches on the east side (the "wild side") are beautiful, and for the most part unspoiled. But, the surf coming directly in is dangerous and not suitable for any kind of water sports. Three divers lost their lives there in 2004. There are a couple of protected coves, marked by restaurants and more tamed beaches, that ARE safe, and have lots of families and childen swimming.
Give "Coconuts" a try on the northern end of the road. Great location, great view (on a small rise over the beach), and great food. Just be wary of the traditional rural Mexico toilet arrangements (you are supposed to put your used toilet paper in the waste basket instead of flushing it—Yuck!).
The main town on Cozumel is San Miguel. It's a funny little place, and smaller than the maps would suggest. The north-south streets (Avenidas) are numbered in increments of 5, so that Avenida 10 is only two blocks from the waterfront. I guess somebody thought that system would make Cozumel look more developed. And the east-west streets have their own system. Odd-numbered streets (Calle 1, 3, 5, etc.,) are on the SOUTH side of town. Even-numbered streets (Calle 2, 4, 6, etc.,) are on the NORTH side of town
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