For snorkeling I would highly recommend Xel Ha. Yes, it costs money, but it's a great day. You don't have to do Xel Ha as a tour - you can take one of the white vans from the main highway directly to Xel Ha for something like $3 - no need for a rental car, or taxi or charter bus. The other option would be bring your own gear and snorkel from Akumal beach - we saw a sea turtle there and it was a great experience.
|