Archaeologists have used a combination of fieldwork and LIDAR technology to uncover evidence of a 2,500-year-old settlement in the upper Amazon.
The dense network of urban centres, the largest known in Amazonia, sits in the Upano Valley of Ecuador, in the eastern foothills of the Andes.
It was occupied from about 500 BCE to 300-600 CE, according to evidence from the sites.
The research team, based in France and Ecuador, has published its findings in Science.
“This discovery raises many questions,” write the researchers in their paper.
“What types of features were built by the pre-Hispanic inhabitants? Were the settlements contemporary and connected to each other? Where did the inhabitants cultivate the large quantity of plants needed for their subsistence?”
The research builds on two decades of archaeological finds in the area, suggesting the presence of a bigger settlement, as well as evidence of several ancient roads.
In 2015, the Ecuadorian National Institute for Cultural Heritage commissioned a LIDAR (light detection and ranging) survey of the area. LIDAR uses a laser to find 3D structures and topography. The researchers analysed this data, which revealed plenty of anthropogenic features.
“The analysis revealed an elaborate anthropogenic landscape,” they write.
“Settlements with standardised archaeological features evidencing a shared cultural background are interconnected by short and long roads.”
This implies, say the researchers, that the settlements were occupied at the same time.
The area’s most common feature is earthen platforms, mostly rectangular and in groups which the researchers believe were buildings.
They’ve also found evidence of drained fields.
“The results of fieldwork and LIDAR analysis demonstrate that the Upano Valley was densely populated around the beginning of the common era,” write the researchers.
“The intimate link between residential and agricultural areas brings to mind the ‘garden cities’ and ‘green urbanism’ described or theorised by other researchers.
“Far from the utopia that these terms imply, however, the garden urbanism of the Upano valley constitutes a concrete, dynamic, and probably contested landscape and provides further proof that Amazonia is not the pristine forest once depicted.”