In the forests of northern Guatemala, a Maya house platform may survive as a low rise of stones. From the ground, it can be almost impossible to distinguish that platform from the surrounding terrain. Airborne laser mapping makes its position clearer. That terrain model can also reveal houses grouped around courtyards, paths leading toward plazas and fields divided by terraces or low walls. Across hundreds of square kilometres, these modest features show how widely Maya communities occupied and altered the landscape.
The Maya Lowlands cover much of the Yucatán Peninsula and adjoining parts of Guatemala, Belize and Mexico. Some cities had temple complexes and palaces at their centres. Beyond them, people lived in smaller communities among gardens, farms, water reservoirs and local ceremonial buildings. Archaeologists have investigated these settlements for generations. Surveying the extensive forest between known ruins, however, demanded so much ground work that regional comparisons remained difficult.
LiDAR, short for light detection and ranging, has allowed archaeologists to examine much larger areas. Since the late 2000s, airborne surveys have mapped tens of thousands of structures as well as causeways, agricultural terraces, altered wetlands, defences and waterworks. The findings support larger estimates of the population of the central lowlands, while also revealing areas where settlement was relatively sparse. Understanding these contrasts still requires excavation and dating to establish what the mapped remains were and when they were used.
How archaeologists map buildings beneath the canopy
LiDAR instruments aboard aircraft send laser pulses toward the earth and measure how long the reflected signals take to return. Many pulses hit the forest canopy, but others pass between leaves and branches and reach the ground. By separating returns from vegetation from those associated with the surface, researchers build a digital terrain model. Slope maps and hillshaded images can bring out features too low to be noticed readily on foot: the edge of a terrace, the rectangular outline of a building platform or the raised line of a road.
A shape on the terrain model still needs interpretation. LiDAR measures the shape of the surviving surface. It cannot penetrate solid masonry, identify a mound’s builders or date their work. Structures that leave no rise above ground may go unrecorded, and a natural outcrop or agricultural stone pile can be mistaken for a building. In their 2024 survey of Campeche, Mexico the researchers explain how they reprocessed survey data, inspected several terrain visualisations and used more than one analyst to assess possible structures. They caution that some small mounds could be non-residential rock piles, so fieldwork is needed to test those classifications.
The distinction becomes especially important when structure counts are used to estimate population. The researchers behind the 2024 Campeche survey worked with laser data first gathered to monitor forests, not archaeological sites. Reprocessing exposed features that the original terrain model had represented poorly. It also let them examine an old sampling concern: surveys concentrated around famous cities might produce unusually high settlement densities simply because archaeologists chose places already known to be important. the new survey reveals substantial variation across the region, with both heavily settled and much quieter districts.
From Caracol to the great Guatemala survey
At Caracol in Belize, Arlen and Diane Chase already knew from decades of excavation that the ancient city extended well beyond its ceremonial centre. An airborne survey gave them a much broader view. Their 2011 research paper covered approximately 200 square kilometres and brought together residential groups, terraced hills and road networks on one map. The survey expanded the existing archaeological picture by showing the extent and connected character of a settlement whose outlying areas had been difficult to document systematically from the ground.
The next major survey was much larger. In 2016, the PACUNAM LiDAR Initiative surveyed 2,144 square kilometres using an approach shared by archaeologists working across several sites. Marcello Canuto, Francisco Estrada-Belli and their colleagues presented the results in a 2018 study in Science. They mapped 61,480 archaeological structures, alongside 362 square kilometres of terraced or otherwise modified agricultural land, 952 square kilometres judged suitable for cultivation and 106 square kilometres of raised causeways. Those figures apply to the sampled area, not the entire Maya world.
Mapped together, these features revealed connections that were difficult to trace through individual excavations. Roads connected household groups and minor plazas with larger centres; terraces spread over slopes around residential areas; and defensive earthworks protected approaches to some settlements. Much of the built and worked landscape lay well outside the great temple groups most familiar to visitors. In places, the apparent gaps between monumental centres were occupied by interconnected communities and farmland rather than untouched forest.
Houses were also easier to overlook than temples. A stone pyramid remains conspicuous even in dense vegetation, while a household platform only a few decimetres high can be missed without careful fieldwalking and excavation. These smaller remains help researchers investigate the number of households, the organisation of residential districts and the food needed to support them. Laser surveys give researchers a more consistent record over broad areas. The identification and dates of the individual features still depend on archaeological investigation.
How many people lived in the Maya Lowlands?
The 2018 PACUNAM team used the density of mapped remains, estimates of how many were occupied simultaneously and assumptions about household size to calculate a Late Classic population of seven to eleven million in the central Maya Lowlands. Their reconstruction concerned roughly 95,000 square kilometres, with a population peak especially around 650 to 800 CE. The 61,480 structures identified by LiDAR came from a much smaller sample. The estimate for millions of inhabitants was an extrapolation from that sample, and depended on assumptions about settlement that the laser measurements could not confirm directly.
A 2025 study by Estrada-Belli, Canuto, Ivan Šprajc and Juan Carlos Fernandez-Diaz brought additional mapping, including reprocessed environmental LiDAR, to the question of Late Classic population and suggested 9.5 to 16 million inhabitants in the central lowlands. The research team’s published summary describes coverage in Guatemala, western Belize and southern Mexico. Residential and agricultural features repeatedly appeared around civic-ceremonial plaza groups, and the researchers reported that nearly every mapped structure was within five kilometres of a medium or large plaza. Such proximity suggests close connections between households and local centres. It cannot establish how those communities were governed or how their food circulated.
Neither estimate is a census. A platform might have supported a residence, kitchen, workshop or storehouse, and buildings surviving side by side might have been erected or abandoned centuries apart. Archaeologists must estimate how many structures represented distinct households, how many people lived in each and what proportion of buildings stood occupied together. The terrain selected for scanning and the treatment of ambiguous low mounds also affect the results. Population ranges preserve those uncertainties better than a single precise-looking total.
The differences are clear in a 2024 open-access study in Antiquity. Luke Auld-Thomas and colleagues re-examined approximately 122 square kilometres of Campeche LiDAR and mapped 6,764 structures. One block contained a substantial urban centre, named Valeriana by the researchers, with monumental architecture and plazas. Another had intermediate settlement density; the third was largely rural. The overall average of 55.3 structures per square kilometre conceals that sharp contrast. Maya urban centres could be extensive without making the whole lowlands a continuous city.
The word ‘city’ also needs care in the Maya Lowlands. Administrative and ceremonial districts were often surrounded by broad residential areas, gardens and productive fields rather than enclosed within the compact boundaries of a walled town. Archaeologists use ‘low-density urbanism’ to describe some of these arrangements, but it does not designate one uniform plan. Caracol, Tikal and the mapped communities of Campeche differed in terrain, water supply, building concentrations and political history. Regional surveys make those differences visible and invite closer study of how each settlement worked.
The raised roads connecting communities
The Maya built raised roads, often called sacbeob in Yucatec Maya, using stone and earth fill to support prepared surfaces. Some linked buildings and plazas within settlements, while others connected more distant communities. Long roads, including the one associated with Cobá in the northern Yucatán, were known well before airborne laser surveys. LiDAR has traced faint embankments farther through dense forests and wetlands, revealing connections between sites too small or remote to have been mapped together previously.
The causeways of Caracol connected its monumental groups with outlying districts and ran through a landscape extensively modified for cultivation. Their construction demanded labour, building material and choices about routes, alongside whatever benefits they offered people travelling to markets, ceremonies or centres of authority. But a road is not proof that the settlements at either end were under the same king. Nor can the terrain model determine whether every branch was in use at the same moment. Archaeologists turn to dated deposits, inscriptions and excavation to investigate those political and chronological questions.
In northern Guatemala, the Mirador-Calakmul Karst Basin study published in Ancient Mesoamerica documented over 177 kilometres of elevated causeways linking Preclassic settlements. The researchers identified 964 settlement clusters in the basin and neighbouring ridges and suggested that many belonged within at least 417 larger sites or settlement hierarchies. They read the roads and large buildings as signs of substantial coordination in the Middle and Late Preclassic. Those categories describe different scales of settlement: a group of structures is not necessarily a city, and the proposed relationships between groups rest on analysis of their architecture and positions.
The detailed shape of a road can also tell researchers why its builders chose a particular route. Some causeways crossed seasonal flooding, joined reservoir banks or led directly to ceremonial plazas; others changed direction or stopped. Such alignments reveal how settlements were physically connected and where communities invested in movement across the landscape. They do not reveal by themselves whether kings controlled the routes, neighbours negotiated their use or local workers maintained them. Their political history varies by place and date and needs evidence beyond the elevation map.
Reservoirs, dams and the problem of the dry season
Water posed an equally serious problem for settlement. Rainfall in the central lowlands is seasonal, while limestone bedrock in many areas allows surface water to drain away rapidly. Communities needed reserves that would last through the dry months. They built reservoirs, dams, channels and modified depressions, sometimes placing them beside roads and residential districts. LiDAR shows where many of these features sit in relation to one another. To establish how a hydraulic system worked, researchers must also examine sediments, construction layers and possible directions of flow.
Tikal’s waterworks had been studied through excavations and sediment analysis long before the recent regional LiDAR projects. Vernon Scarborough and colleagues presented that evidence in their 2012 study of Tikal’s water and land use. Among the features they described was the Palace or Causeway Dam, which served both as a roadway and as part of the reservoir network. The team also discussed a proposed switching station and filtration arrangements. These discoveries came from sustained archaeological work, not from a LiDAR image alone.
Different reservoirs also had different histories of water quality. A 2020 geochemical and molecular study detected mercury, phosphates and potentially toxic cyanobacteria in deposits from two major Tikal reservoirs. A separate 2020 study of the Corriental reservoir reported quartz and zeolite at Corriental and proposed that they formed part of a system intended to filter water. The first findings raise questions about pollution and its consequences; the second concerns a possible means of improving water quality elsewhere in the city. Neither can be extended to every Maya community, and the contamination findings alone do not establish the cause of Tikal’s political decline.
Reservoirs needed care long after construction. It required a suitable catchment, measures to reduce leakage, channels to capture runoff and continued upkeep. Some dams also supported roads, so transport and water management could be part of the same investment. A dry season or prolonged drought would test the effectiveness of that infrastructure, including for households beyond the central plazas. LiDAR identifies possible connections between features; excavation and environmental analysis explain how they were built, maintained and changed.
Farming within the Maya urban landscape
Farmers worked land within and around these settlements. Maya farmers grew maize, beans, squash and other crops, using different techniques according to soil, rainfall and terrain. Managed woodland, household gardens, terraced slopes and altered wetlands all contributed in different places. Terrace walls reduced soil loss on hillsides, while raised plots and channels controlled excess water in wetter ground. The 362 square kilometres of modified agricultural terrain documented by PACUNAM in 2018 gives a measure of how much land had been worked within the surveyed region.
At Caracol, the Chase surveys showed how agricultural terraces ran among and around residential neighbourhoods. Fields could therefore be closely associated with the people cultivating them, rather than lying in a distant rural district beyond the city. The investment visible in the terrace network suggests work carried out over many generations. But walls visible together today need not have been cultivated at the same time. Excavated soils, plant remains and dated occupation deposits provide a more precise account of changes in farming than surface shape can supply.
The Campeche survey shows how easily agricultural features can be mistaken for house remains. The 2024 survey found heavily altered land, with dense residential clusters, field walls and smaller stone piles, alongside much less developed areas. Some low piles may reflect farming activity rather than homes. Counting all of them as residences would inflate an estimate of population. At the same time, dwellings constructed largely from perishable materials might leave so little relief that a laser survey misses them. Both errors must be considered before a map becomes a demographic model.
The concentration of farms and residences around plaza groups also raises questions about authority. The 2025 regional study found patterns consistent with organised local communities linked to larger centres, but it did not establish ownership of fields or determine whether produce moved through markets or tribute demands. We cannot read rates of taxation from a terrace wall. Household archaeology, the distribution of goods and written records where they survive are needed to investigate exchange and obligations. The maps establish the close physical association of agriculture and settlement; their economic relationships require further evidence.
Defensive earthworks and the limits of political maps
The lowlands’ defences have become easier to study as well. Forest makes it difficult to follow ditches and banks across a ridge, particularly beyond monumental centres. PACUNAM’s 2018 survey mapped substantial defensive earthworks among its roads and settlements, some placed on elevated ground or commanding approaches. At El Zotz, subsequent fieldwork investigated a hilltop fortified position with ditches and ramparts. One feature was reported at roughly nine metres high. That measurement describes an earthwork within a defensive complex, not a continuous nine-metre-high wall around the city.
Fortifications suggest that conflict shaped movement and settlement. A ditch could restrict access to an exposed ridge, while a bank might once have carried timber defences now lost. Yet the outline of a mound or trench usually gives no date for its construction and no name for the person who ordered it. The identification of a feature as military may itself depend on excavation and comparison with surrounding landforms. Even where the purpose is reasonably clear, it is difficult to connect an earthwork to a particular battle from topography alone.
The territorial reach of Maya rulers is harder to plot than their roads. Royal inscriptions record conflicts, political alliances and rulers, but a causeway passing near a named kingdom cannot automatically be assigned to that king. Some routes may have crossed political boundaries or survived a change of dynasty. Archaeologists therefore combine the spatial relationships shown by LiDAR with inscriptions, ceramics and other chronological evidence. Only then can a regional map begin to reveal the histories of neighbouring political communities.
Aguada Fénix and monumental building before Maya kings
Laser surveys have also mapped monumental works far older than the Classic Maya cities. At Aguada Fénix in Tabasco, Mexico, Takeshi Inomata, Daniela Triadan and colleagues recognised an enormous artificial platform in a landscape where its shape had scarcely been apparent on the ground. Excavation and radiocarbon dates placed major building work in the early first millennium BCE. Their 2020 paper in Nature described a platform approximately 1,400 metres long and 10 to 15 metres high, accompanied by nine causeways. The discovery raised questions about the assumption that monumental Maya-region buildings developed only after highly stratified royal institutions appeared.
Aguada Fénix belongs to the early Middle Preclassic, centuries before the dynasties documented by Classic-period inscriptions. Its builders did not leave a corresponding series of monuments naming their kings. Inomata and colleagues suggested that shared ceremonial activity and cooperative construction could have mobilised labour on a large scale. The lack of royal portraits or clearly identifiable palaces is relevant to that interpretation. It cannot demonstrate that the society had no inequalities or that everyone worked voluntarily.
A subsequent 2021 study in Nature Human Behaviour recorded 478 rectangular or square ceremonial complexes across the Olmec region and western Maya Lowlands, broadly dated to around 1050–400 BCE. Their plans show a widespread architectural practice, and the authors considered whether the earlier Olmec centre of San Lorenzo had influenced its development. The 478 complexes were not identical versions of Aguada Fénix. They differ in size, layout and date, allowing the researchers to trace both the circulation and alteration of architectural ideas.
In November 2025, a full open-access study in Science Advances expanded the known extent of Aguada Fénix. New excavations and LiDAR analysis revealed nested cross-shaped axes stretching roughly nine kilometres along one direction and 7.5 kilometres along the other. Causeways, corridors and canals helped define this planned landscape. Some canals reached 35 metres in width and five metres in depth, and the builders had constructed a dam beside Laguna Naranjito. The excavators found that some canals had never been completed. The scale of the proposed design therefore extended well beyond the large central platform.
One cross-shaped deposit at the centre contained blue azurite to the north, green malachite to the east and yellow ochre to the south, together with marine shells. The excavators see this arrangement as evidence of directional symbolism and propose that the site’s greater cross-shaped design represented an ordered cosmos. The coloured materials are physical findings; the interpretation of the builders’ beliefs remains a reconstruction because they left no written explanation. The 2025 study also cautions against assuming that these people necessarily spoke a Mayan language, despite cultural connections with later Maya societies.
Aguada Fénix shows what LiDAR can reveal about ceremonial landscapes centuries older than the Classic cities. It allows researchers to follow a Preclassic ceremonial plan across several kilometres, just as it traces later houses, fields and roads. The communities responsible for such early monuments may have been organised very differently from the later dynastic kingdoms. Establishing that difference depends on excavated construction sequences, offerings and dates rather than the terrain model by itself.
What the new maps can prove, and what remains uncertain
Across the lowlands, mapped houses and infrastructure show how far communities modified the terrain. Houses, terraces, reservoirs, roads and fortifications now appear in districts whose conventional archaeological maps had little to show. The same surveys also reveal sharp variations in density, from large clusters of buildings to sparsely occupied tracts. Monumental centres represent only part of the settlement evidence, but the opposite assumption, that the entire forest had once been built up, is equally inconsistent with the surveys.
Dating those remains is harder than locating them. LiDAR records the features still visible on the surface, even when they belong to different centuries. Auld-Thomas and colleagues noted in the 2024 Campeche research that their northern and southern sampled areas should not automatically be treated as contemporary. Pottery sequences, stratigraphy and radiocarbon dates are needed to establish which places were occupied together and when. Laser maps can direct that work more efficiently; they cannot give the structures an age.
That caution applies to the demographic figures. The earlier seven-to-eleven-million range and the later 9.5-to-16-million estimate concern populations reconstructed for the central lowlands, not observed censuses or figures encompassing every Maya-speaking region. They depend on settlement densities and assumptions about occupations and households. The large numbers indicate that densely occupied and carefully managed landscapes supported substantial populations, while future fieldwork may change the ranges and clarify how rural areas related to local political centres.
Precise archaeological maps can also expose vulnerable sites to looting. Publishing the coordinates of unprotected remains makes them easier to locate. Decisions about survey access and ownership of information also concern institutions in Guatemala, Mexico and Belize and the Maya communities whose heritage these sites represent. Collaboration and the responsible handling of sensitive coordinates are therefore part of regional archaeological practice. Explaining a discovery publicly does not require making every vulnerable location easy to find.
The maps show the distribution of homes, fields, roads and waterworks across areas once investigated largely in isolation. They also give archaeologists a basis for comparing how these arrangements changed between the Preclassic and Classic periods. Answering them will require dated excavations, evidence from the environment and scrutiny of historical sources alongside LiDAR. The forest has concealed much of the built terrain, but the traces alone do not tell us how its inhabitants organised their lives.
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