For a day outing from Playa del Carmen, Cancun, or from a cruise ship, you must consider Xcaret (ish-ka-ret) - an ecological park, adventure outing, and beach all in one.
Located halfway between touristy Cancun and the coastal Mayan city of Tulum, and only three miles from the ferry dock in Playa del Carmen, the location is perfect for a one day diversion.
The wide range of activities appeal to many - adventure seekers can dive on a coral reef or interact with the dolphins (for and extra charge). History buffs can tour Maya sites, others can wander through the park to see butterflies, birds, wild animals, and mushrooms. Everyone can relax on the beach or even get a massage (again extra).
There are two rivers flowing through the partk - explorers can either swim along ( with a life vest) or snorkel to enjoy the underwater life. One of these is underground with light shining through the openings in the cavern walls - the other passes through a recreated mayan village.
Admission is about $45 - $50 per person, but you can spend all day enjoying the park - shower - change, and stay into the evening for a two hour spectacular Mayan performance in a huge theatre involving more than 200 performers.
When cruise ships are in port it can be busy - go on a weekend if possible and it's worth toting along your snorkeling gear (it's expensive to rent).
Unfortunately we found no discounts for this park. The Occidental Grand Xcaret is attached to this park via manmade canals and admission here is free during your stay.
I have read that it is unlimited admission everyday, but when we visited last summer it was limited to one visit per stay after the 15th of August - before that it was daily. If this is important to you, call the hotel directly and ask for the specific dates that you will be staying there.