On Mexico's Yucatán Peninsula, warm blue rivers thread below the earth's surface. With a bit of diligence, an adventurous swimmer can discover the pathway to the gods
Sally Gall
| Credit: Sally Gall

Like pilgrims who trek to far-flung places to catch the sun at equinox, I have come to Dzitnup cenote, in the center of the state of Yucatán, Mexico, at 7 a.m., to see a renowned sunbeam pass through the earth's crust and strike the surface of an underground lake. With temperatures hanging above 100 degrees, I also plan to immerse myself in the tepid, azure water.

To get here at dawn, I've followed a rope handrail down into a muggy cavern lit by electric bulbs, where I wait alone and in silence. At my feet, coal-black catfish drift through the water in dreamtime. High overhead, a lone subsonic bat wheels among stalactites and dangling aerial roots. As the slim wand of sunlight stabs the darkness from above, I'm mesmerized by the shimmering blue water and the bright white reflection undulating on the rock overhead.

Too soon the spell is broken. The tourist buses pull up, and within minutes the cavern is crowded and noisy, the sunbeam a spotlight on splashy antics, the catfish gone. If I'm going to get what I hoped for—something akin to those moonlit summer dips I took in the quarries of my childhood—it won't be in this Yucatecan version of a public swimming hole, extraordinarily lit though it may be. To bask in more tranquil and restorative waters, I'll have to head toward the capital city of Mérida, then plunge into the realm known as the Anillo de Cenotes.

The limestone plateau that forms the Yucatán Peninsula was once a coral reef in an immense inland ocean. When the Ice Age lowered sea levels, groundwater seeped through cracks in the limestone, creating the vast network of caves through which all the Yucatecan rivers flow today. Where ceilings wore thinnest, they collapsed, exposing round sinkholes—the natural wells of sweet freshwater the Maya called dz'onot (and the Spanish corrupted into cenote).

In 1988, Charles Duller, a NASA researcher scanning satellite images for signs of those ancient water sources, noticed a nearly perfect semicircle of sinkholes around Mérida—the Anillo de Cenotes, or Ring of Cenotes. At the same time, scientists seeking evidence that a catastrophic meteor had altered the global climate and caused the mass extinction of the dinosaurs 65 million years earlier realized that this pocky 105-mile-wide arc of cracked earth could be the vestige of an impact crater. Four years later, Canadian geologist Alan Hildebrand and his team found the landing site of a six-mile-wide meteor just north of Mérida, near the coastal village of Chicxulub (in the Mayan language, x is pronounced sh). To my mind, this means that when I do finally dive into the perfect swimming hole, I'll be jackknifing darn close to the bull's-eye of the single greatest cataclysm life on earth has ever known.

At the ruins of Chichén Itzá, near Dzitnup, I once visited the famous Well of Sacrifice. Looking at it, you'd never guess that the ancient Maya considered this cenote, a roped-off pit of scummy green water, to be the most sacred place on earth. (Its significance was shrouded in mystery until archaeologist Edward Thompson dredged the well's depths in 1904, recovering not just the sacrificial remains of men, women, and children but also priceless gold offerings.) To the Maya, cenotes were portals to Xibalba, the Mayan underworld, where the sun slept at night and deities like Chac Xib Chac, the god of sacrifice, lived. Across the Yucatán, sacrificial candidates were thrown into these sinkholes at dawn on the Mayan New Year. At noon, those who had managed to survive were pulled out and queried about the upcoming year. It was believed they had been close enough to hear the gods whispering their plans for mankind. To me, that translates as he who swims in a cenote plays closest to the ancient gods. The temptation is too strong to resist.

HALF AN HOUR EAST OF MÉRIDA, THE PENINSULA'S FIRST AND MOST important colonial city, I steer my rental car into Tixkokob, a hammock-making center. Ten minutes later I'm pulling into Hacienda San José Cholul, one of three meticulously refurbished 16th- and 17th-century manor houses where I'll sleep between swims. After a short siesta on a rope-hung bed, I head for the pool to establish a benchmark of comparison. Overhead, nighthawks knit the evening air while mariachi duets waft from the shadows. I notice references to the ancient civilization that once dominated this area. The pool is lined with the same chicle-and-lime formula the Maya used to seal their aqueducts and cisterns. Its steps are like those of the nearby pyramids, while a monolithic slab at its center harks back to the commemorative stone stelae the Maya often placed before them.

Gabriel Castillo, a manager at the hacienda, directs me to a quiet sacbé (white road). It leads to three cenotes, he says, one of which is sure to suit me. As I drive down the gravel ribbon, hundreds of fist-sized sulfur-yellow and chartreuse butterflies move in front of me like petals in the breeze. I have always loved the first snowflakes of winter, and I can't escape the thought that these mariposas are summer's snow. I stop the car and step into a blizzard of yellow and green and orange. Though recent rains explain the mass migration, the butterflies' delicate dance reminds me that there is magic in the Yucatán. I have bathed in butterfly wings.

On I drive. At Chunkanán, where several mini-gauge railroad lines converge, I am greeted at a store called Tres Cenotes by a man named Silvario. With a warm smile he asks if I'd like to see the cenotes. "Si!" I reply. "And to swim!" He spreads a horse blanket on a four-by-five-foot flatbed railcar called a truk and offers me a clean New York Yankees cap for shade. After hooking up Bolas, his chestnut pony, to the truk, he shakes the reins and we're off on a clanky glide along the rails that still serve this hacienda town.

As Bolas picks up speed, we pass a healthy patch of pineapple-y henequen plants. Related to the prickly agave, which is the source of tequila, henequen was used by the Maya to make twine for hammocks, sandals, and other objects. It's the raison d'être for the rails, the smokestacks scattered across the landscape, and the prosperity of the haciendas themselves. In fact, it was the demand for wheat-sheaving twine in the United States that started shipments from the nearby port of Sisal, sparking a boom in the late 1800's. Five hundred haciendas converted from Mayan settlements to growing "green gold," and until the revolution in 1910, Mérida had more millionaires than any other city its size in the world.

As thunderheads build in the afternoon heat, Silvario assures me that the prettiest, más bonito of the three cenotes is also el ú ltimo, the farthest one. I decide to bypass the first two and head straight to the best, Bolon Chohol. Brilliant blue birds with cuckoo-clock tails flash out of the small porthole entrance as I begin to descend the long ladder made of rail sections. I have no idea what I'll find. Reaching the bottom, I dive into the warm tarn, come to the surface, and hear the clop of horse's hooves and the zing of rails: two more flatcars pull up, carrying a dozen swimmers from Mérida. My dream of swimming solo with the underworld gods may be a silly gringo fantasy, but I now have a rule of thumb: Avoid cenotes in towns, on major roads, and on functioning rail lines. They draw crowds.

The next day, at the southwestern extreme of the Anillo de Cenotes, I check into the 11-room Hacienda Santa Rosa de Lima, the former estate of a Spanish nobleman. This place is less grand than the other haciendas I've visited, more intimate. And while I haven't yet found my postcard cenote, the pool is a welcome substitute in the midday heat. Small and elegant, it recedes through four arches into an artificial grotto topped by a breezy dovecote—a room where you can roost in a hammock for an after-swim nap. Margarita in hand, balancing effortlessly in the rope-slung net, I make a plan: tomorrow, I will drive directly to Hacienda Temozón, in the very heart of the Anillo de Cenotes. And I will get a guide.

Twenty-four hours later, the palatial, stately Hacienda Temozón—which even has its own church on the 15-acre estate—makes the heat infinitely more bearable. My guide is Temozón's groundskeeper, Fidel Cocum, a descendant of the last ruling pre-Conquest clan in the Yucatán. When he appears with a basket of fluffy rolled towels, bottled water, and flowers, I get the feeling this cenote safari is off to a good start. And with four cenotes within a 20-minute drive on serviceable sacbés, I have plenty of choices.

We spend the afternoon checking them all. I descend the long, steep metal ladder that leads directly into the dark, mysterious water of Kankirixche, where I share the stillness with no one. I follow the cement steps of Chihuohol past a rubble pile, once a small pyramid, and into an empty amphitheater-shaped cenote overhung with the mud nests of chittering swallows. At Sambula, I head down square Mayan temple stones, the kind that haciendados once pilfered to pave their courtyards.

Near the village of Cacao, past a tumbledown hacienda at the end of a secluded but car-friendly sacbé, we stop in a quiet, shade-spattered spot. Here, Fidel tells me, is Yáx Ha (Green Water). "Careful," he warns in Spanish, pointing to a rickety ladder that leads into the 30-foot-wide chamber. Startled, I gasp aloud when I see the shaft of laser-blue light penetrating the gin-clear water in the pool's center, frozen in space and time like a titanic sapphire crystal. I have no doubt this is it, my fantasy plunge. When I slide into the 82-degree water, powder blue and soft as velvet from traces of calcium carbonate, the vibrant beam oscillates at my presence. The bottom, 60 feet below, is so clearly defined that I'm sure I can reach down and touch it. And it is quiet. So quiet that when I close my eyes I can hear meteors hurtling through the vacuum of space, the wings of a thousand yellow butterflies, and whispers I'm sure are in Mayan.

I wait, but other swimmers never come.

Then I lie back and float, fairly certain I am close to the gods.

Hacienda San José Cholul, Hacienda Santa Rosa de Lima, and Hacienda Temozón 800/325-3589 or 52-99/443-637, fax 52-99/448-484; doubles from $234.