Previously undiscovered ancient cities stretching hundreds of acres have been found in the depths of the Llanos de Mojos savannah-forest in Bolivia thanks to new technology.
International researchers from the UK and Germany have found the settlements, believed to have been built between 500 and 1400 AD, that have been hidden by nature for centuries, the Daily Mail reports.
Dense vegetation had concealed the ancient ruins from previous surveys, but this group of researchers used airborne laser technology for the first time in the Amazon.
Their findings have been published in the journal, Nature.
The evidence is seen as proof of a permanent settlement in the area in pre-Hispanic times, and one that is understood to have observed sustainability and conservation.
“So the entire region was densely settled, a pattern that overturns all previous ideas,” co-author Professor Carla Betancourt said.
“For the first time, we can refer to pre-Hispanic urbanism in the Amazon and show the map of the Cotoca site, the largest settlement of the Casarabe culture known to us so far.”
The settlements feature towering terraces covering 54 acres -the equivalent of 30 football pitches – and 69ft-tall conical pyramids.
A vast network of reservoirs, causeways and checkpoints, spanning several miles was also discovered within the vast lands.
The findings challenge the notion that Amazonia was untouched or pristine, but rather beg the question it was home to early urbanism by indigenous peoples.
“We long suspected that the most complex pre-Columbian societies in the whole basin developed in this part of the Bolivian Amazon, but evidence is concealed under the forest canopy and is hard to visit in person,” José Iriarte from the University of Exeter said, the Daily Mail reports.
“There are monumental structures just a mile apart connected by 600 miles of canals long raised causeways connecting sites, reservoirs and lakes.”
The Mojos Plains, on the southwestern fringe of the Amazon region, flood several months a year during rainy season, making them unsuitable for permanent settlement.
However, in recent decades evidence has emerged of irrigation, earthworks, large towns and causeways and canals that often lead for miles in a dead straight line across the savannas.
The lidar technology surveys terrain with a laser scanner attached to a helicopter, small aircraft or drone before the vegetation is then digitally removed.
A 3D image is produced or a digital model of the earth’s surface.
The process revealed two remarkably large sites of 363 acres and 778 acres in a dense four-tiered settlement system.
The architecture consists of stepped platforms topped by U-shaped structures, rectangular platform mounds, and conical pyramids.
The study shows that the indigenous people not only managed forested landscapes, but also created urban landscapes in tandem – providing evidence of successful, sustainable subsistence strategies but also a previously undiscovered cultural-ecological heritage.
“'Our results put to rest arguments that western Amazonia was sparsely populated in pre-Hispanic times. The architectural layout of Casarabe culture large settlement sites indicates that the inhabitants of this region created a new social and public landscape,” said co-author Dr Mark Robinson of the University of Exeter.
The research, by the Deutsches Archäologisches Institut, the University of Bonn, the University of Exeter, and ArcTron 3D is published in the journal Nature.
