The city, discovered by chance in the southeastern state of Campeche, has been named Valeriana, after the nearby lagoon. Archaeologists uncovered pyramids, sports fields, causeways connecting different areas, and amphitheaters. According to experts, Valeriana ranks just behind Calakmul—the largest Mayan settlement—in terms of population density.
The complex of structures was revealed in the dense jungles of Mexico through geospatial technology known as LiDAR, which uses laser beams to scan hidden objects and create three-dimensional maps of the terrain.
The Fortunate Find of a Graduate Archaeologist
Luke Old-Thomas, a graduate student at Tulane University in the U.S., stumbled upon the traces of this unknown city while sifting through unexamined materials from a LiDAR survey during an online search for relevant data.
“I was somewhere around the 16th page of a Google search when I found a laser survey conducted by a Mexican environmental monitoring organization,” he explained. But when Old-Thomas processed the data using archaeological methods, he saw what others had missed: a vast ancient city that, at its peak (between 750 and 850 A.D.), could have housed between 30,000 and 50,000 residents.
According to Professor Marcello Canuto, a co-author of the study, this discovery helps reshape Western perceptions that the tropics were places where “civilizations perished.” In reality, this part of the world was home to advanced and complex cultures.
Researchers also reported that Valeriana exhibits “capital city” characteristics and is second only to the opulent city of Calakmul, located about 100 kilometers away, in terms of urban density. Archaeologists believe that the locals may have suspected ancient ruins lay beneath the earth mounds.
The city, covering approximately 16.6 square kilometers, featured two major centers with large buildings situated two kilometers apart, connected by dense construction and causeways. The team discovered two plazas with temple pyramids where the Maya worshipped their gods, stored treasures like jade masks, and buried their dead. There was also a court where they likely played ball games. Additionally, scientists noted signs of a reservoir in Valeriana.
Overall, Luke Old-Thomas’s team surveyed three different jungle sites and found 6,764 buildings of various sizes, according to BBC reports.
The study confirmed that the collapse of the Maya civilization, which began around 800 A.D., was partly due to overpopulation in cities that could not withstand climatic challenges. The Spanish conquest of the region in the 16th century also contributed to the destruction of the Maya city-states.
The findings were published in the journal Antiquity.
What’s the Secret to the Resilience of Ancient Maya Cities?
Luke Old-Thomas noted, “You can see columns along the facades of buildings used for public purposes. They are in very good condition.”
So, what is the secret of the Maya? How did their renowned architecture withstand the ravages of time? Recent studies have shed light on the methods employed by builders of that era. These methods included adding materials such as rubber, glue, and volcanic ash to mixtures to enhance strength.
Juan Carlos Fernandez-Diaz, an engineer from the University of Houston who participated in the latest research, has been mapping areas of Mesoamerica using LiDAR for the past 15 years. He confirmed that Maya architecture has remarkably survived.
One reason for this is that the Maya built with stone, which does not decay like wood. They also created a special mortar that prevented stone structures from crumbling into piles of rubble, BBC reports.
For this mortar, builders used natural materials such as blood, eggs, and natural rubber obtained from local trees. When researchers analyzed the mortar taken from stones in the main pyramid of the archaeological site of Witzin, they found traces of saturated fats typical of natural rubber. Maya masons used it as a binding agent along with fine clay to create a strong mortar that held the stone masonry together.
Another team of archaeologists studied mortar samples from excavations at Rio Bec in southeastern Campeche and found evidence that the Maya added volcanic ash to the mixture to strengthen it.
It has long been known that the Maya were skilled at making lime plaster, which was used to coat and protect interior floors or walls, bind stones together, and decorate building surfaces.
Archaeologists discovered that the plaster was particularly strong and durable because the Maya often added the juice of chukum and chiote tree bark to the mixture. Meanwhile, extracts from guasuma trees acted as a fixative, preserving the color layers in the lime plaster.
Organic plants also prevented the material from dissolving in rain, which is crucial for the tropical climate with its frequent hurricanes bringing heavy rains.
Other studies have pointed to another reason why the ruins of Maya cities have endured for so long. The dense vegetation made these ruins hard to access, but it also protected them from development and looting.