If you take a cruise that stops in cozumel, you have a couple of choices.. if you're looking to party and drink a lot, there are obvious choices and pub tours. However, if you want to scuba, snorkel, relax, be entertained, eat well and generally have a good time for a couple or family, the place to go is Chankanaab. The park is a wonderful way to spend the day. The snorkeling and diving are amazing, complete with underwater park trails. The animals in the shows are treated very well, and the shows are impressive. The walking trail through Mexican history is great. Try the tortillas made in the replica village..

It's a great place. It's one of the few places in the Caribbean you can buy LEGAL black coral jewelry (they have special dispensation to collect black coral that naturally breaks off and make jewelry out of it). Make sure you keep the receipt so if customs bothers you coming back into the states, you can show them what you purchased was legal. Black coral is endangered, and tourists often have their purchases confiscated coming back into the states.

One further suggestion - the ceviche at the restaurant in the park is amazing.