Photograph by Mark Thiessen, National Geographic
Not all Maya ruins are picturesque temples that rise above the landscape and reach to the clouds. Some lie hundreds of feet belowground in the watery depths of remote, flooded caves. Why did the ancient Maya exert such incredible effort to build within these dangerous, virtually inaccessible labyrinths? And how? Underwater archaeologist Guillermo de Anda descends into the darkness laden with ropes, scuba gear, and curiosity to tell their remarkable story.
With thousands of caves and cenotes (sinkholes) lacing the Yucatán Peninsula landscape, how does de Anda target prime sites to explore? He began by diving into a 450-year-old book filled with testimony from the Spanish Inquisition. Zealous to eradicate the Maya's religious practice of human sacrifice, Spaniards interrogated and tortured Indians to elicit locations of cenotes where ceremonies took place.
"The chronicles recorded names of villages and descriptions of priests going out of their way to reach specific cenotes that held special religious significance, places where people had worshiped for centuries," de Anda reports. He was the very first to connect the dots between Inquisition testimony, sacred texts, and mysterious remains discovered in caves. The puzzle his detective work seeks to solve depends on his skills as an archaeology scholar, an expert in human bones, and a high-level cave diving instructor.
"Exploring these caves is very demanding," he admits. "The ancient Maya liked to make it hard; they searched for extremely distant places. So we know the harder it is to get there, the better our findings may be."
De Anda's team of four disappears into caves for 12 or more hours at a time, draped with equipment, hacking apart overgrown entrances, rappelling down 100-foot vertical drops, diving into 200-foot pools, swimming horizontally along narrow passageways, squeezing through tiny openings, dodging swarms of bats, crawling on floors moving with snakes and scorpions, and never forgetting how to find their way out.
"When we literally reach the ends of the Earth, and find skeletons that match the age and sex of victims described in Inquisition chronicles, it's all worth it," he says.
But bones are only the beginning. De Anda's arduous explorations reveal construction projects that would be breathtaking aboveground, yet were created by hand, belowground, hundreds and thousands of years ago. Magnificent walled-off chambers with 50-foot ceilings and carefully cleaned and flattened floors. Altars bearing traces of burnt offerings. Secret doorways leading to submerged temples and pyramids. A sculpture of an elaborate headdress atop a dignified head. A mural dancing with jaguars and deer. And, most astonishing of all, a massive, perfectly paved road stretching more than a hundred yards into a watery abyss.
"Caves were considered thresholds to the afterlife, the realm of the gods, powerful spaces filled with important energy and supernatural forces," de Anda explains. "Since they believed everything from fertility to rain originated in caves, the Maya went to great lengths to stay on good terms with this fearsome spirit world."
De Anda linked this set of beliefs with his own discoveries to answer why such monumental building projects may populate cave depths. Ancient sacred texts depict the legendary journey to the afterlife as a perilous course strewn with steep canyons and terrifying obstacles. In those legends, the path hits a crossroads and turns sharply west, ending at a deadly underground body of water. In Maya religious tradition, west signified the direction souls moved after death. "The amazing road that we discovered and followed may have been built to symbolically re-create and simulate the path to the afterlife described in Maya mythology," he says. "It also took a sudden turn west, continuing above and below water, through multiple chambers, before vanishing into the cave's deepest lake."
How was a road built and traveled upon if vast sections of it lay underwater? It wasn't, de Anda asserts. "We believe it was built during a time of great drought, when water levels were down. This may also indicate why the Maya went to such monumental efforts. They were in such desperate need of water, they took extreme measures to reach and worship the gods, offer sacrifices, and appeal to them for rain."
The road would have been dry if the water level had been just two or three feet lower. Subsequent rises in water level submerged buildings and bones and became a perfect preservative. De Anda credits the excellent condition of many artifacts to the cenotes' deep freshwater environment, which is devoid of oxygen, stays at a consistent temperature, and maintains almost total darkness.
Experts in ancient climate concur that severe droughts in the ninth and tenth centuries likely caused huge drops in water level, even sea level. "These droughts match the age of remains and materials we found," de Anda notes. "In one cenote, after diving horizontally for about 60 feet, we came to a small niche at the end with a perfectly preserved ceramic pot dating to the drought period. It didn't swim there, and these waters have no currents. It was placed."
Other caves yielded sacrificial knives, jade, human and dog skulls, and a stone inscribed with hieroglyphics, all dating to the same years of drought. Recent discoveries from a cenote at Mexico's famed archeological site Chichén Itzá further confirm this theory. Just a few feet beneath the waterline, the bones of six humans were found alongside carefully placed jade beads, ceramic pots, and various animal bones. De Anda suggests that "this was a ritual offering that may have served as a desperate attempt to please the gods during a time of brutal drought."
For him, it is definitive evidence that these extreme shifts in the water level occurred. "This archaeological evidence of historically documented changes in climate long ago may help analyze dramatic storms and droughts happening today," he says. "The Maya, particularly those in the northern lowlands of the Yucatán Peninsula, were true survivors who appreciated how dependent humans are on the natural world. This profound respect for nature is a lesson we can all learn from them."
Grateful for a career that combines science and adventure, de Anda shares that "the moment of discovery is thrilling, but it's also a huge responsibility. My light may be shining on human remains or artifacts for the first time in 2,000 years. I have the privilege to stand here and the responsibility to translate it for the rest of the world."
Latest Explorer News
Explorers have discovered what might be the oldest evidence of humans in the Americas.
A labyrinth filled with stone temples and pyramids in 14 caves—some underwater—have been uncovered on Mexico's Yucatán Peninsula, archaeologists announced.
Legend says the afterlife for ancient Mayas was a terrifying obstacle course in which the dead had to traverse rivers of blood, and chambers full of sharp knives, bats, and jaguars.
In Their Words
Water and the underground world of caves were very sacred to the Maya. Our discoveries reveal new clues about their culture, beliefs, and struggle to survive through climate changes.
Guillermo de Anda
Guillermo de Anda and his team find that the most wonderful discoveries can happen in the most unlikely of places.
Guillermo de Anda dives into remote, flooded caves and sinkholes in Mexico, searching for signs of the ancient Maya.
See vintage photos of Maya site exploration, including sacred temples and cenotes.
Meet Our Archaeologists
Dr. Fredrik Hiebert, archaeologist and explorer, traces ancient trade routes.
Our Explorers in Action
Meet female explorers who have pushed the limits in adventure, science, and more.