Archaeologists working deep in the Amazon rainforest have discovered an extensive network of cities dating back 2,500 years.
The highly structured pre-Hispanic settlements, with wide streets and long, straight roads, plazas and clusters of monumental platforms were found in the Upano Valley in Amazonian Ecuador, at the eastern foothills of the Andes, according to a study published in the journal Science on Thursday.
The earliest and largest urban network of built and excavated features in the Amazon to date has been discovered as a result of more than twenty years of investigations in the region by a team from France, Germany, Ecuador and Puerto Rico.
The research began with fieldwork before using a remote sensing method called light sensing and ranging, or lidar, which used laser light to detect structures under the thick tree canopies.
Lead author of the study Stéphen Rostain, archaeologist and director of Research at the French National Center for Scientific Research (CNRS), described the discovery as “unbelievable”.
‘Advanced engineering’
“The lidar gave us an overview of the region and we could really appreciate the size of the sites,” he told CNN on Friday, adding that it showed them a “whole network” of excavated roads. “The lidar was the icing on the cake.”
Rostain said that the first people who lived there, 3,000 years ago, had scattered small houses.
However, between about 500 BCE and 300 to 600 CE, the Kilamope and later Upano cultures began to build mounds and set their houses on earthen platforms, according to the study’s authors. These platforms would be arranged around a low square plaza.
Data from LiDAR revealed more than 6,000 terraces within the southern half of the 600-square-kilometer (232-square-mile) area surveyed.
The platforms were mostly rectangular, although some were circular, and measured about 20 meters by 10 meters (66 feet by 33 feet), according to the study. They were usually taken around a square in groups of three or six. The plazas also often had a central platform.
The team also found memorial complexes with much larger platforms, which they said probably had a civic or ceremonial function.
At least 15 clusters of complexes identified as settlements were discovered.
Some settlements were protected by ditches, and there were roadblocks near some of the large complexes. This suggests that the settlements were exposed to threats, external or as a result of tensions between groups, the researchers said.
Even the most remote complexes were linked by footpaths and an extensive network of straight, larger roads with curbs.
In the empty buffer zones between complexes, the team found features of land cultivation, such as drainage fields and terraces. These were linked by a network of pathways, according to the study.
“For that reason, I call these garden cities,” said Rostain, who added: “It’s a complete revolution in our paradigm about the Amazon.”
“We have to think that not all Indigenous people (people) in the rainforest are semi-nomadic tribes lost in the forest looking for food. They are a great variety, a variety of situations and some of them were related to (an) urban system, to (a) stratified society,” he said.
The overall organization of the cities suggests “high engineering” at the time, according to the study’s authors, who concluded that the urbanization of the Upano Valley garden provides “further proof that Amazonia is not the pure forest once depicted .”
Rostain said we should imagine pre-Columbian Amazonia “like an ant’s nest,” with everyone busy with activities.
Similar sites can be found across America
According to landscape archaeologist Carlos Morales-Aguilar, a postdoctoral fellow at the University of Texas at Austin, this newly discovered urban network closely aligns with other sites discovered throughout the tropical forests of Panama, Guatemala, Belize, Brazil and Mexico. was not involved in the study.
He called the study “groundbreaking,” telling CNN that it provides “concrete evidence of early urban planning in the Amazon but also greatly contributes to our understanding of the cultural and environmental heritage of Indigenous societies in the region.” this.”
In 2022, Morales-Aguilar was part of a team of researchers who used LiDAR to discover a vast site in northern Guatemala, where hundreds of interconnected Mayan cities, towns and villages, as well as a 110-mile (177-kilometer) network of raised stone paths connecting communities.
He said the results of this latest study match the advanced techniques in agriculture and urban planning he observed in northern Guatemala and provide “new insights into the complexity of these early societies.”
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