Archeologists have found evidence of medieval urban and agricultural networks in the surroundings of the ancient city of Angkor Wat, the world’s largest religious complex. The new findings were discovered through new laser technology capable of spotting some things invisible to the naked eye.

Damian Evans and his colleagues assured in the paper soon to be published in the Journal of Archaeological Science, that they found traces of extensive networks surrounding the monumental stone temple complex at Angkor Wat. The findings could help understand the Khmer culture better and throw into question some traditional assumptions about the empire’s decline, as reported by the New York Times.

Cambodia's cities discovered
Archeologists have found evidence of medieval urban and agricultural networks in the surroundings of the ancient city of Angkor Wat. Credit: Damian Evans/Cambodian Archaeological Lidar Initiative

The team used a high-tech laser called Lidar, which stands for light detection and ranging, to detect objects and create precise maps of the ancient networks. These structures surrounding the temple were built of wood and thatch which has long rotted away, Evans stated.

“You could be standing in the middle of the forest looking at what appear to be some random lumps and bumps,” Evans told the New York Times. “But they might actually be evidence of old excavated ponds or built-up roadways. All of these things left traces in the surface of the landscape that would not make sense to you without a more detailed picture.”

The team spent about 90 hours in a helicopter directing laser scans into the jungle to analyze the area. The resulting images were so intricate that some objects were seen lying next to a tiny anthill, Evans commented.

The findings were the results of a combined work from the French Institute of Asian Studies in Paris, the Cambodian national authority responsible for protecting Angkor Wat, and the ministry of culture and fine arts.

Angkor Wat is a UNESCO World Heritage site, among the most important ones in Southeast Asia. It is also considered one of the ancient wonders of the world. The complex was constructed from the early to mid-1100s by King Suryavarman II at the height of the Khmer Empire’s political and military power. It was among the largest pre-industrial cities in the world, according to

Cambodia's cities discovered
Angkor Wat is the largest religious monument in the world, with the site measuring 162.6 hectares. Credit: Wikipedia

However, experts have always debated that there must be some others civilizations or prove of networks in the surroundings of the religious site. It is like assuming that Europe’s population was only located in the center of its biggest and most important churches, they said.

Changing the perspective

The archeologist community had believed for years that the ancient Khmer civilization collapsed in the 15th century when it was invaded by Thai armies, which forced the population to relocate to southern Cambodia.

However, Evans commented that their laser maps showed no evidence of relocated, dense cities in the south and that it was not clear if such mass migration ever happened. According to Chanratana Chen, a Cambodian academic at the University of Sorbonne in Paris, the new finding has changed even his own perception of the Angkor Wat temple complex.

Cambodian people commonly referred to the ancient city as a small one, this could have changed thanks to the work made by Evan’s team members. His work will be presented as well on Monday at the Royal Geographic Society in London.

“The new results show us that Cambodia was a much more advanced civilization than we thought, especially about the management plan of the city and irrigation system to improve agriculture in the area,” Chen, who was not involved in the research, wrote in an email.

Tourists probably will not be exploring any time soon the “mounds in the ground,” Evans commented. The place will be subject to further exploration and excavation aimed to collect physical evidence about the networks.

According to Evans, it is likely there are similar discoveries elsewhere in Southeast Asia, possibly in Burma and even the Americas, where archeologist might unearth more secrets about the remains left behind in the 6th-century Mayan Empire.

The high-tech laser used

Even though this is the biggest finding ever related to the laser examination among the archeologist community, the technology was created in the 1960s, just after the laser was invented, as reported by the Washington Post.

It worked like a radar that uses radio waves to find foreign objects, this time through the wooded area. Lidar acts like a common laser, and it is the same technology used by the police to measure the speeding cars on the interstate.

The previous Lidar technology could only shoot about 2,000 pulses per second, which was obsolete to the kind of work Evans and his team planned to do. However, some upgrades made the laser shot 600,000 pulses per second. At that rate, enough lasers make it through the vegetation to offer information on what is underneath.

The technology offered the possibility to draw some pretty accurate maps of the place, similar to those made by the team on the ground, which performed the work by hand while using machetes and shovel to advance in the forest.

“There was a French team that had been working in the central Angkor areas and they covered nine square kilometers the old-fashioned way,” Evans said, meaning they used machetes to cut through the vegetation and shovels to reach the trace materials that indicated where a canal or a roadway might have been.

The traditional way took team many years to map about nine kilometers, which Evans said his team was able to do with the same accuracy in a mere one to two hours using lidar.

Source: The New York Times