LiDAR Discoveries in the Ancient Americas Are Changing Archaeology

For most of the history of archaeology, landscapes like this looked empty. Dense forests, remote valleys, wetlands and plains where little evidence of large settlements could be seen from the ground. To archaeologists working on foot, many of these places appeared only lightly occupied, sometimes even untouched. But a new tool is beginning to LiDAR, a technology that uses laser pulses from aircraft to map the ground surface. This allows researchers to digitally remove vegetation and reveal the terrain beneath. And when archaeologists began scanning parts of the Americas with LiDAR, something unexpected started to appear. Hidden landscapes, not just isolated ruins, but patterns of human activity that were nearly impossible to see before. Across forests, mountains, wetlands and temperate woodlands, LiDAR is revealing roads, platforms, agricultural systems and settlement networks that extend far beyond the monuments archaeologists already knew. These discoveries don't replace what archaeologists understood about ancient societies in the Americas, but they are filling in the spaces between sites. And in doing so, they are beginning to rewrite something important. Not the existence of ancient civilizations, but the scale of the landscapes that they shaped. One of the clearest examples comes from the eastern slopes of the Andes in Ecuador. The Upino Valley lies along the edge of the Amazon Basin, a region where dense vegetation makes large-scale archaeological patterns difficult, if not impossible, to recognize. For decades, archaeologists working in the valley documented scattered earthen platforms and other features. But the broader landscape remained hard to interpret. From the ground, the sites appeared isolated. So researchers scanned the valley using LiDAR. And when the forest canopy was digitally removed, a very different picture emerged. The scans revealed thousands of raised platforms arranged across the valley floor. Straight roads connected many of them, forming organized pathways between these clusters of structures. Some of these roads may extend for kilometers. Instead of scattered settlements hidden in the jungle, the valley appears to contain an entire network of communities connected by infrastructure. Discoveries like this shift the kinds of questions that archaeologists are asking. The issue is no longer simply whether people lived in the region. The evidence suggests they did, and in organized communities that spread across the landscape. What once looked like empty forest now appears as a place shaped by long-term human activity. The Amazon is only one example. In other regions, LiDAR isn't just revealing new sites. It's showing that places archaeologists already knew about are part of something much larger. Deep in the cloud forests of northern Peru lies a site called Gran Pajatan. Archaeologists have known about this site for decades. Stone structures decorated with intricate carvings stand along a mountain ridge built by the Chachapoya people. But the terrain surrounding Gran Pajatan is steep, it's rugged, and it's heavily forest. Surveying the surrounding slopes on foot is extremely difficult. So although the core complex was well documented, archaeologists could not easily determine how far the surrounding settlement extended. And LiDAR provided a way to see that landscape. When the forest canopy was digitally removed, dozens of additional structures appeared hidden across the ridge and nearby slopes. Terraces, buildings, and architectural features extended well beyond the central ruins. What had once appeared to be a single ceremonial complex now looks more like a part of a broader settlement network embedded within the surrounding mountains. Gran Pajatan was not standing alone in the forest. It was part of a much larger landscape of human activity. And when archaeologists began scanning entire regions instead of just individual sites, the scale of these hidden landscapes became even clear. In northern Bolivia, the Llanos de Mojos stretch across vast seasonal wetlands of the Amazon basin. During the rainy season, large areas flood. And during the dry season, the region appears as open grassland dotted with rivers and lakes. At first glance, it looks almost entirely natural. Archaeologists had long known that ancient communities had lived in this region. Small settlement mounds and scattered artifacts suggested long-term occupation here. But how large populations sustained themselves in such a dynamic environment, that remained uncertain. But LIDAR provided that new perspective. And when researchers scanned those wetlands, geometric patterns began to appear across the floodplain. Networks of raised agricultural fields, canals, and settlement mounds stretched across the landscape. These raised ridges allowed crops to grow above seasonal floodwaters, while channels helped manage the drain water and flow. What looked like untouched wetlands was, in many places, a carefully engineered agricultural system. Instead of small communities adapting passively to the environment, the evidence suggests something much more complex. Entire ecosystems were being modified to support large human settlement. And discoveries like these raise an even larger question. If LIDAR can reveal engineered landscapes and settlement networks across individual valleys and wetlands, then what might appear when archaeologists scan the entire region? Across parts of Mexico, Guatemala, and Belize, the forests of the Maya lowlands conceal one of the most studied ancient civilizations in the Americas. For more than a century, archaeologists have excavated temples, pyramids, and cities rising above this jungle canopy. But even here, much of the surrounding landscape remained difficult to see. Recent LIDAR surveys have mapped enormous areas of the Maya lowlands. Instead of focusing on individual cities, these scans reveal entire regions all at once. And the results have been striking. Thousands of previously undocumented structures appear beneath the forest. Platforms, houses, terraces, and causeways spread across the terrain. Instead of isolated cities surrounded by empty wilderness, many areas appear densely occupied with communities connected across that landscape. The monumental pyramids and temples that first drew explorers to the region may have only been the first most visible elements of a much broader and more populated environment. And the pattern does not stop in the tropical forest. Even in landscapes that appear subtle or lightly modified, LIDAR is beginning to reveal traces of extensive human activity. In many parts of North America, the archaeological record looks far less dramatic. Instead of towering pyramids or massive ruins, the evidence often appears as low ridges and shallow depressions or even small earthen mounds. These features can easily disappear beneath forests and grasslands and plowing. For decades, many of them remained difficult to recognize from the ground. But LIDAR scans are beginning to reveal patterns within these landscapes as well. In some regions, networks of agricultural ridges emerge beneath forest cover. In others, earthworks and subtle terrain modification become visible when viewed from above. Individually, these features might seem minor, but together they suggest something very important. Even landscapes that appear natural today often contain traces of these deliberate human modifications. These fields were shaped, and the water was managed, and environments were gradually transformed to support large settlements. Taken together, these discoveries reveal a broader pattern. Across the Americas, LIDAR is exposing landscapes that once supported organized communities, agricultural systems, and infrastructure extending far beyond the ruins archaeologists first studied. The sites were never isolated, and they were part of a much bigger environment shaped by human activity. And for a long time, many of these regions were interpreted as sparsely occupied or only lightly modified. And that impression was understandable then. From the ground, much of this just remained hidden and unseeable. But LIDAR allows archaeologists to see landscapes now at an entirely different scale. And instead of focusing on individual sites, entire regions can now be mapped and analyzed. And those landscapes reveal something very important. Ancient societies across the Americas were not simply adapting to their environments. In many places, they reshaped them. These roads connected settlements, and the fields altered ecosystems, and networks of communities extended across regions that once appeared only empty. LIDAR is not replacing traditional archaeology. Excavations, artifacts, and careful field work will remain essential, but by revealing the hidden landscapes between known sites, this technology is adding a new dimension to how the past can be understood. And as more of these landscapes are mapped, the picture of the ancient Americas can continue to grow. And not just in detail, but in scale. And in our understanding of a people that were once forgotten. I'm Christine. Thank you for watching My Forgotten Past.