The Yucatan Peninsula, particularly the northern half, is very dry. There are no rivers on the surface, and marshlands are rare and transitory; it is said that the Mayan Empire was weakened (though not collapsed, despite what some history books still suggest) by drought. The empire remained well watered, however, thanks to limestone karst sinkholes accessing underwater rivers, which they called ts’onotes.
Cenotes, as we call them today, were both sacred and strategic, wells of extraordinarily clear, naturally filtered fresh water available to townspeople throughout the northern Yucatan. Most are connected by massive underground river systems that cave divers document to lengths of 235 kilometers (146 miles) in the case of Ox Bel Ha—and from the name (Mayan meaning “Three Paths of Water”), it’s clear that the Mayans were well aware of this hidden hydrogeology.
There are around 6,000 cenotes in the Yucatán Peninsula and around Cancun, most of them arranged in a loose ring believed to delineate the “Chicxulub Crater,” an ancient meteor crater hypothesized to have caused the global cooling event that wiped out the dinosaurs. Perhaps 2,500 of them have been explored, and the 25.5°C (78°F) waters of several are open to swimmers, cenote-gazers, snorkelers and divers.
The most famous and accessible is the Cenote Sagrado (Sacred Cenote), an unusually large and murky pool around which Chichen Itza was built. While access to the water is prohibited, archaeologists have uncovered all manner of sacrifices beneath the water—gold, jade, pottery, rubber, human bones and rather mysteriously, ancient wood and textile artifacts that should have long since rotted away.
Those seeking a more personal experience with a cenote can find it close at hand. In the town of Valladolid, just outside the ruins, you can swim in the city’s rather opaqu Vaci Cenote, or grab a cab 7 kilometers (4 miles) out of town to the much prettier Dzitnup Cenote, with crystal clear water, stalactites, cool lighting and kid-friendly activities.
Parque Ik Kil, about 3 kilometers from Chichen Itza in Piste, has a huge, deep, well developed cenote with easy access thanks to the stone staircase and beautiful blue water. Yokdzonot Cenote, about 10 minutes away from Chichen Itza in Yokdzonote, is a bit more laid back, with swimming, horseback riding, a hotel and campsite.
The town of Cuzama is simply surrounded with cenotes, and has made it quite the local tourist attraction. Guides can take you, by buggy or on horseback, on a tour of three or more photogenic cenotes. Chelentun Cenote is considered one of the Yucatan’s loveliest because of its brilliant blue water.
Because the Mayans depended on cenotes for fresh water, several others are close to worthwhile ruins. Yaxunah Archaeological Site, about halfway between Chichen Itza and Yaxcaba, has a cenote with stair access, swimming and a nearby cultural center. Close to Merida, Cenote San Ignacio offers swimming and other family-friendly amenities, complete with the full sound- and light-show treatment, beneath an 8-meter (26-foot) limestone dome dripping with stalactites. Sistema Dos Ojos, near Tulum, specializes in cave dives where you’ll enter one cenote and exit, via underground river, from another.
There are even a few fully developed water parks, clustered around Playa del Carmen, that are geared to foreign tourists. Check out Labna Ha, with caving, swimming, snorkeling, diving and a zip line; Hidden World Cenote Park, with diving and other attractions; or fanciest of all, Xel Ha, in Playa del Carmen, with ruins, rides and cenotes.
There are more spots to enjoy cenotes, many of them developed with very basic amenities—perhaps just lockers, a rope ladder and snack carts—by local Mayan communities who would appreciate a share of Yucatan’s tourist dollars. Diving outfits often specialize in the cenotes less traveled, and can take you on an underwater adventure as easy or extreme as you’d like. Look around online or ask tour operators once you’ve arrived; they’ll find the right cenote for you.