Archaeologists in Guatemala have uncovered an unprecedented network of 60,000 ancient Mayan features such as palaces and elevated highways, according to an exclusive report by National Geographic. The discovery is being called a “megalopolis,” and suggests that we’ve been vastly underestimating the sophistication of the Mayan civilization at the height of its power 1,200 years ago.
Researchers owe the breakthrough to the cutting-edge remote sensing method Light Detection and Ranging, better known as LiDAR. Usually taken aerially, LiDAR recordings channel light into laser pulses that measure the distance from the air down to a given point on the surface of the Earth, according to the National Oceanic and Atmospheric Administration.
These particular images covered a region of more than 800 square miles of the Maya Biosphere Reserve of northern Guatemala. All together, it’s the largest LiDAR dataset ever to be used in archaeological research, according to National Geographic.
“The LiDAR images make it clear that this entire region was a settlement system whose scale and population density had been grossly underestimated,” Thomas Garrison, an Ithaca College archaeologist and National Geographic Explorer who specializes in applying technology like LiDAR, told National Geographic.
LiDAR allowed the archaeologists to digitally erase the jungle’s top canopy layer from aerial images, essentially photoshopping them out. Without the canopy in the way, the massive pre-Colombian civilization was revealed for the first time in centuries.
What the researchers saw upends assumptions about pre-Columbian life. “We’ve had this western conceit that complex civilizations can’t flourish in the tropics, that the tropics are where civilizations go to die,” Tulane University archaeologist Marcello Canuto, also a National Geographic Explorer, told National Geographic. “But with the new LiDAR-based evidence from Central America…we now have to consider that complex societies may have formed in the tropics and made their way outward from there.”
The Mayan culture was at its peak from roughly 250 A.D. to 900 A.D., according to the MesoAmerican Research Center. During that era, known as the Maya Classic period, the civilization was twice the size of medieval England—and much more densely populated than previous researchers had suspected, according to National Geographic.
In the past, when still limited to ground-based study, archaeologists had believed the Mayan civilization in Central America to be diffuse and loosely connected. But the megalopolis suggests that it was actually more comparable to civilizations of ancient Greece or China. The LiDAR scans showed densely packed urban centers, sophisticated irrigation systems and advanced engineering achievements like highways that had been raised off the ground so they could still be used during the rainy season.
“LiDAR is revolutionizing archaeology the way the Hubble Space Telescope revolutionized astronomy,” Francisco Estrada-Belli, also a Tulane University archaeologist and National Geographic Explorer, told National Geographic. “We’ll need 100 years to go through all [the data] and really understand what we’re seeing.”