Start with pickup at your hotel, then begin the trip to the Tulum Archeological Site, among the most dramatic ancient cities on the Yucatan Peninsula, with stone fortifications overlooking a white sand beach. Learn about the history and culture of the Mayan people, with free time to photograph the ruins before leaving the site. Continue to the Mexican Caribbean in an air-conditioned vehicle. Get fitted with snorkeling gear, and slip into the water to swim over the coral reef (the fee for Conservation of the Marine Fauna is not included in this tour, and must be paid during the tour). The afternoon is all about the natural world: follow your guide into a cave that’s bristling with stalagmites and stalactites, then take a walk through the jungle, listening to a forest chorus of tropical birds and animals. Visit the nearby Cenote Xtun to cool off with a swim in the fresh, limestone-filtered water.