One of many cenotes—water-filled sinkholes—that dot the Yucatán peninsula, Cenote Zací is located within the small city of Valladolid, which was built on the site the Mayan settlement of Zací from which the landmark takes its name.

Though somewhat more open than some other cenotes (and thus a bit less claustrophobic), Cenote Zací offers a cool, shady respite from the tropical heat, with a sloped passage with stairs carved right out of the natural rock leading down behind stalactites to the water's surface. The cave is about 150 feet across, and 260 feet deep, much of which is filled with water. Many people, including many locals, join the eyeless black fish that swim in its deep, cold waters, though the proximity to municipal sewer pipes scares off some tourists. Some daring visitors have even been known to dive from a high ledge midway up the side of the cave.

The Yucatán peninsula is said to have as many as 6,000 such sinkholes pocking the jungle landscape. Although the Cenote Zací may be the only one located in the midst of a largely urban surround. So whether one goes in for swimming or not, the Cenote Zací offers the calm shade and scenic cave views that most cities simply can't offer.