Archaeological Discovery: Ancient cities 2,500 years old emerge from the Amazon, revealing a hidden past

The recent discovery in Ecuador was made possible through the use of mapping technology known as Lidar. Ancient villages, now hidden by forest, which were connected by roads, were home to up to 30,000 inhabitants, a population comparable to that of London in the Roman era.

Laser sensor identified network of ancient cities linked by roads in the Ecuadorian Amazon - Photo Reproduction/Antoine Dorison/AP/picture alliance

In the vast, lush landscapes of the Amazon, an extraordinary archaeological discovery is revealing insights into a previously unknown ancient past. Archaeologists unearthed a group of ancient cities that were home to thousands of inhabitants approximately 2,500 years ago. These cities are now hidden beneath the dense vegetation of the Amazon rainforest.

More than two decades ago, archaeologist Stéphen Rostain,who is director of research at France's National Center for Scientific Research, noticed a series of underground roads and mounds of earth in Ecuador. However, at the time, the French researcher confessed: "I wasn't sure how it all connected." Rostain is one of the scientists who shared this fascinating discovery in the scientific journal Science, published on Thursday (11).

Ancient Metropolises Under the Forest

A recent survey carried out using laser sensor technology revealed that these locations constituted an intricate network of cities connected by roads and canals, hidden in forested hillsides of the Andes, and which existed for approximately a thousand years. According to Rostain, it is a lost valley of cities. Settlements in the Upano Valley, located in eastern Ecuador, were inhabited between about 500 BC and 300 to 600 AD, a period that roughly aligns with the Roman Empire in Europe.

Surprisingly, this occurred more than a thousand years before any other complex society in the Amazon that was known. For example, Machu Picchu, in Peru, was built in the 15th century. This discovery, therefore, substantially alters the understanding that was previously held about the history of ancient civilizations in the Amazon, which, as previous evidence suggested, supposedly lived as nomads or in small settlements.

The researchers discovered five large urban centers and ten smaller ones in an area of ​​300 square kilometers. Each of these sites featured a dense concentration of residential and ceremonial structures. In all, evidence of 6,000 mounds of earth was identified, presumably fundamental to the construction of these buildings. The cities were arranged interspersed, with rectangular agricultural fields between them. These areas were surrounded by hillside terraces, in which inhabitants grew a variety of foods, including corn, cassava, and sweet potatoes. These findings corroborate previous discoveries from excavations in the region.

Location

The region is situated in the shadow of a volcano, providing fertile soil for agriculture, but may also have contributed to the ruin of society. Wide, straight roads connected the various cities, while streets snaked between homes and neighborhoods. of each village. The main roads, 10 meters wide, extended for distances ranging from 10 to 20 kilometers.

“We are talking about urbanism,” says study co-author Fernando Mejía, an archaeologist at the Pontifical Catholic University of Ecuador.

An Advanced Society in the Jungle

Although it is challenging to estimate populations, the site was home to at least 10,000 inhabitants, possibly as many as 15,000 or 30,000 at its peak, according to archaeologist Antoine Dorison, co-author of the study. This number is comparable to the estimated population of London in the Roman era, demonstrating a dense occupation and an extremely complex society.

Archaeologist José Iriarte of the University of Exeter in the United Kingdom noted that it would have taken an elaborate system of organized labor to build all these roads and thousands of earthen mounds. He highlighted that, unlike the Incas and Mayans, who built with stone, the population in the Amazon generally did not have stone available and used mud in their constructions. Even so, the volume of work carried out is impressive. It is worth mentioning that Iriarte did not participate in the research. He highlighted how the Amazon, often considered a "pristine wilderness with only small groups of people", is revealed to be much more complex in light of recent discoveries about its past.

Mapping technology

The most recent discovery in Ecuador was made possible thanks to the use of mapping technology known as Lidar. This innovation enables researchers to see through the dense forest blanket and reconstruct ancient archaeological sites hidden beneath it. The discovery of an ancient urban network in the Upano Valley highlights the long-neglected diversity of ancient Amazonian cultures, a panorama that archaeologists are only beginning to unravel.

Recently, evidence of rainforest societies that predate European contact has been found in different parts of the Amazon, including Brazil and Bolivia. According to Rostain, "there has always been an incredible diversity of people and settlements in the Amazon, not limited to a single form of life," and researchers are still in the process of learning about them.