For a real change of pace when visiting Cancun and the Riviera Maya, indulge in the ultimate adventure by swimming with whale sharks - the gentle giants of the ocean.
Whale sharks are in the area from May - September, although they are most prevalent in July and August when the plankton they feed on is most abundant.
Measuring up to 40 ft and weighing up to 15 tons, they don't have teeth and pose no threat to humans.
Their mouths - which can extend up to five feet - are always open so that they can filter out enough plankton and small fish needed to feed their enormous bodies.
When you're swimming nearby, just don't make any sudden movements and make sure to stay away from their tails so that they don't 'slap' you accidentally when they turn to swim away.
Several companies in the area have tours, which can be booked through your hotel concierge or directly at the dock. Tours typically leave at dawn.
This is no ordinary snorkeling trip, but it is one you'll never forget.