The tops of the towering temples at Tikal peek out from the canopy of the Petén forest, but hidden deep under the cover of the dense jungle in this part of lowland Guatemala are the remains of many more Maya sites. With visibility and accessibility on the ground a challenge, archaeologists have taken to the skies to map some 2,100km2 of the Maya Biosphere Reserve using LiDAR. Some of the results so far have come as a great surprise.
By looking closely at changes in elevation on the ground revealed by the scans, researchers working on the PACUNAM LiDAR Initiative (PLI) have identified some 60,000 artificial features in the Reserve, ranging from small isolated houses to far-reaching roads and drainage networks. The newly found structures build a picture of Maya cities that are more expansive, more interconnected, and more involved with land-management than previously thought.
Even in Tikal, perhaps the most familiar and widely researched of the survey’s nine main target areas – which also include El Zotz, La Corona-Achiotal, Holmul, Naachtun, Uaxactun, Xultún-San Bartolo, El Perú-Waka’ (see feature on p.24), and El Tintal – there have been some unexpected revelations. At the very centre of the city, the scans show that what was previously thought to be a natural feature is, in fact, a monumental pyramid, some 25m in height. Given its prominent location and stature, this could be the tomb of a ruler, but fieldwork at the site will be needed to investigate this interpretation.
One other transformation in our knowledge of Tikal is that the city looks to be three or four times bigger than was thought before. Settlement surrounding the centre stretches out into what is now jungle to the very limit of the LiDAR survey, and probably further beyond. The PLI’s researchers believe that the unexpectedly high number of buildings at Tikal were home to some 250,000 people, significantly more than the previous population estimate of 60,000.
It is a trend that we can see across the Maya Lowlands. Squares in the LiDAR survey mark where masonry structures stand, building a new picture of populated areas in the spaces between known cities. The urban spread can be substantial. At the Preclassic city of El Palmar, for instance, LiDAR has shown that the sprawling site is 40 times larger than had been thought. Altogether, these more densely occupied sites across the Maya Lowlands had an estimated population of up to 15 million people.
Not only were these cities larger than expected, and some of the land around them inhabited, but they were also better connected and the land worked more extensively. As Francisco Estrada-Belli from Tulane University, the director of the Holmul Archaeological Project, remarked: ‘Seen as a whole, terraces and irrigation channels, reservoirs, fortifications, and causeways reveal an astonishing amount of land-modification done by the Maya over their entire landscape on a scale previously unimaginable.’
Previous theories prevalent in Maya studies have treated the cities as largely isolated and self-sufficient, but LiDAR has highlighted many causeways linking urban centres to nearby shrines and other more distant sites. The largest number of these have been found in the Naachtun region, and the widest (up to 80m across) in Tikal. Taken together, the evidence for these causeways and a particularly high concentration of road construction in the southern lowlands points to an extensive network of interconnected Maya communities.
Fields and fortifications
Still outside the cities, the survey has found signs of further manipulation of the landscape and intense agricultural activity in the form of channels built in grid-like patterns to manage waterflow. In the valley near Holmul, more than 10,000 acres of wetland were drained and irrigated, turning the land into arable fields. More signs of cultivation, low stone walls, and terraces have been detected around cities like Xmakabatun.
Maya water-management can also be seen in the many reservoirs revealed by the PLI. They are a common feature at many of the cities surveyed. Again at Holmul, the inhabitants built a dam to catch surface run-off from the plazas, which they stored in a reservoir with a capacity of 20,000m3 – enough water for 10,000 people for 18 months. Over in Naachtun, large reservoirs near the centre would have served the inhabitants in that part of the city, while smaller reservoirs scattered around the outskirts would have provided water for the outer residential areas.
Reservoirs like these could be used by the city’s inhabitants when under siege, which the results from the survey are suggesting was a very real threat. Until recently, there has been little evidence for large-scale warfare in the Maya world, but now defences at many Preclassic and Classic sites, beyond the already known walls around Tikal and Naachtun, are emerging.
About 20km west of Tikal, LiDAR has uncovered a large fortress on top of a steep slope, defended by trenches and supplied with water by reservoirs on nearby summits. Further from the city, a remote pyramid was identified on a hilltop, whose summit was levelled by hand. The team has interpreted this structure as a watchtower, a new feature found at a number of other sites, including near the Classic city El Zotz. There, as well as ramparts on the surrounding hillsides, the survey identified causeways that connect a series of watchtowers along the length of a 10km ridgeline.
As with the demographics, connectivity, and agricultural activity, the scale and intensity of the defensive infrastructure showcases the impressive ability of the Maya to control their landscape. Thomas Garrison, Assistant Professor at Ithaca College and co-director of the El Zotz Archaeological Project, commented on the finds: ‘Maya warfare has been a topic of investigation for decades, often focusing on the fall of the Classic period sites. LiDAR reveals the physical manifestation of these past conflicts in a way that proves that they were a defining factor of ancient Maya culture, and likely shaped the emergence and development of some of their greatest cities.’
Only about a tenth of the entire target area has been mapped so far, and expectations are high for further revelations both in cities and across the Maya landscape.
The PLI is organised and funded by the Fundación PACUNAM (Patrimonio Cultural y Natural Maya). The international consortium of archaeologists and researchers in related fields includes Marcello A Canuto and Tomás Barrientos (La Corona Regional Project), Thomas Garrison and Yeny Castillo (El Zotz Archaeological Project), Francisco Estrada-Belli (Holmul Archaeological Project), Philippe Nondédéo and Lilian Garrido (Naachtun Archaeological Project), Milan Kovácˇčand Sandra Ventura (Uaxactun Regional Archaeological Project), Mary Jane Acuña and Varinia Matute (El Tintal Archaeological Project), and Damien Marken (Waka’ Archaeological Project).
Images: PACUNAM/Garrison/Proyecto Arqueológico El Zotz.