Take a swim in an area with the whale sharks, the largest fish on the planet, on this tour from Cancun. Hop aboard a boat with a biologist guide and head to the waters surrounding Isla Mujeres, Contoy and Holbox, where you'll snorkel alongside these gentle giants. This tour offers both a small-group option as well as the opportunity for a private swim with just your travel companion or group. Hotel pickup and drop-off is also included. Please note: this tour is offered seasonally, from May to September.