In the popular imagination, Cambodia calls to mind two polarizing images: Angkor Wat and the nation’s bloody recent history under the iron-fisted rule of dictator Pol Pot and the Khmer Rouge. As the nation gradually emerges from the trauma that was its 20th century, archaeologists are beginning to venture back into its dense, steamy jungles where significant discoveries await—among them, the ancient Khmer city of Mahendraparvata.
“Several decades of conflict and civil strife have meant that, until the 1990s, modern archaeology had more or less passed Cambodia by,” Damian Evans, head of the University of Sydney’s archaeology center in Siem Reap, told The Diplomat. “We’ve arrived at a point where Cambodia has one of the world’s richest archaeological landscapes, that also happens to remain one of the least-studied. It has enormous archaeological potential.”
Mahendraparvata (Mountain of the Great Indra) is located on the plateau known as Phnom Kulen, where in 802 AD King Jayavarman II declared himself the divinely sanctioned ruler of Cambodia, giving rise to the Khmer Empire, which famously built the city of Angkor 40 kilometers to the southwest and came to dominate the region for the next 600 years. The site has long been known about in the West, with French archaeologists hunting for it in the 1880s armed with 10th and 11th century Sanskrit inscriptions. While they found a number of Hindu temples on the site, the bulk of the significant discoveries remained underground. In the late 1960s the search for the buried city came to a standstill when the nation became embroiled in a bloody civil war, followed by the horrors of the Khmer Rouge.
It was not until another French archaeologist by the name of Jean-Baptiste Chevance launched the Archeology and Development Foundation (ADF) Phnom Kulen Program in 2008 that serious attention was once again focused on the site. Alongside exploring the site, ADF also invests in development on the plateau, which is home to some 4,000 people who survive by “slash-and-burn farming, illegal logging and poaching,” as noted by journalist Daniel Otis, who ventured into the dense jungles of northern Cambodia along with Evans and a team of archaeologists and cartographers. The ADF also introduced the Apsara National Authority on the plateau, which is now run by a team of a few dozen local villagers who guard and maintain these archaeological sites in close collaboration with the archaeologists on site.
According to Chevance, a number of factors put Angkor in the spotlight while Mahendraparvata waited to be unearthed, among them: the religious significance of Angkor, the difficulties associated with accessing the site on Phnom Kulen, and the fact that it is all but buried in important forest cover. “The Angkor complex is much denser than Mahendraparvata,” Chevance told The Diplomat. “However, the urban organization (of Mahendraparvata) is strictly organized and orientated in a natural environment which is not a flat plain like the site of Angkor, but is rather chaotic (valleys, cliffs, rivers).”
Defining the contours of this geographically complex site would not be possible without the use of a technology known as Lidar (light detection and ranging data), which is revolutionizing archaeology today. In a nutshell, cartographers and archaeologists are using Lidar to map out the contours of Mahendraparvata, with Canadian company McElhanney handling the technical side. This breakthrough technology beams billions of laser pulses down from a helicopter to collect data points, which are then used to create a 3-D map of the site’s topography.
Chevance explained: “So ‘lost city’ is not the appropriate term as you do not deploy such a technology in a virgin area, like playing darts on a map…It is the result of years of research.” With Lidar, there is a lot to uncover not only in Mahendraparvata but across the country and in archaeology worldwide. “I’m expecting this technology to spread and be used more often in the future,” Belgian cartographer and photographer Stephane De Greef, who was involved with mapping the site, told The Diplomat.
De Greef added, “The results in Phnom Kulen are just a small part of the Lidar survey conducted in 2012 in Cambodia (about 15 percent) and equally amazing discoveries occurred around Angkor Wat and other temples around it. Other sites in Cambodia, Thailand or Myanmar could bring equally amazing results.”
The sheer extent of tree coverage and ground vegetation makes many of these sites highly difficult to access with a spade in hand. Evans explained that “these will be the focus of future Lidar missions and we anticipate equally exciting discoveries in those places, some of which are completely subsumed by jungle.” Other areas ideally suited to Lidar exploration include those inhabited by the Maya and civilizations in Sri Lanka, he added.
De Greef explained that prior to the introduction of Lidar, the scale of Mahendraparvata “had been dramatically underestimated both in size and land use intensity. We had actually missed 95 percent of it until this new technology allowed us to realize that fact! Similar cities were sprawling in the Angkor plain around the Bayon temple, Ta Prohm and other temples, but this one is among the oldest found so far.”
Based on the results of the survey so far, the article penned by Otis in The Global and Mail reveals that a complex network of dikes, canals, reservoirs, appeared to have once run through the site, which was roughly the size of modern day Phnom Penh. Highways – the largest one being 60 meters wide and eight kilometers long – ran through Mahendraparvata, which had a massive pyramid at its center. The city appears to have been linked to other settlements by networks of roads and temples appear to have dotted the urban space.
Yet, all of this for now remains underground. What will be found once it is unearthed?
“The vast majority of the construction in these medieval cities of Southeast Asia was of non-durable material like wood and thatch, so it has all disappeared from the archaeological record,” Evans said. “When we excavate, the main type of material remains are ceramics—fragments of broken pots and so on—which through scientific investigation can actually tell us a great deal about the kind of activity that took place in any given areas.”
He continued, “With the amount of material that we can see from the Lidar, to excavate it all would take lifetimes. So we’ve begun targeting specific areas within the urban complex for excavation that we think will maximize the archaeological information that we can glean for the minimum effort of digging.”
Although Lidar costs can soar to around $1,000 per square kilometer of ground surveyed, Evans says in the end the price tag is worth it. “We could have been getting those same data from ground-based surveys using machetes and ground survey equipment. But it would have taken us decades to acquire so many points over such a wide area. When you consider how much that would have cost us (a fortune), all of a sudden Lidar starts to look extremely cost-effective.”
He added, “The technology will revolutionize our understanding of those civilizations in the next few years, and indeed has already started to do so.”