Legend has it that when Genghis Khan died in 1227, his soldiers murdered the builders of his tomb and all the people who witnessed his funeral procession. The soldiers themselves were then killed, leaving no one alive who could reveal the location of the notorious warlord’s final resting place. For the past several years, scientists have enlisted thousands of volunteers to go through high-resolution satellite images of vast swathes of Mongolian landscape, seeking any unusual features that might lead them to Khan’s tomb.
On August 18, 1227, Mongol leader Genghis Khan died from unknown causes while leading a military campaign in China. According to legend, Khan’s soldiers murdered anyone who witnessed his funeral procession back to the Mongol capital of Karakorum, as well as the 2,000 people who attended his funeral, before being executed themselves on the orders of Khan’s successors.
The area where historians suspect Genghis Khan may be buried (in an unmarked grave) is considered sacred land for Mongolians; its name, Ikh Khorig, translates to “the Great Taboo.” The first archaeological expedition of the region in 800 years took place in 1989, and though it identified more than 1,300 underground sites that might be graves, none of these sites have been excavated due to hostile public opposition.
Beginning in 2010, a team led by Albert Yu-Min Lin, a research scientist at the University of California, San Diego, embarked on an innovative—but less invasive—approach to solving this long-running mystery. Via the Internet, Lin’s Valley of the Khans project invited interested members of the public to join the search for Khan’s tomb by visiting a National Geographic website and scanning thousands of high-resolution images of Mongolia taken from orbital satellites. As part of this “virtual exploration,” the scientists asked volunteers to flag known features and sites–including roads, rivers and any ancient or modern structures–as well as anything out of the ordinary in the landscape.
Now, in a recent issue of the journal PLOS One, Lin and his colleagues have shared the study’s initial results. They reveal that in the first six months of the project, more than 10,000 volunteers spent a total of some 30,000 hours (the equivalent of 3.4 years) scanning the images, which covered a total of roughly 2,300 square miles of land. After the “explorers” tagged more than 2.3 million sites, researchers then narrowed the list to only 100 accessible locations, and a field team verified 55 of those with archaeological significance. Some of these are thought to be gravesites spanning the Bronze Age to the Mongol era, though it appears none are Khan’s actual tomb.
Though it’s not certain what the next steps are for the virtual exploration project, the study authors believe the work done so far has clear potential to aid further in the search for Khan’s tomb, as well as for other sensitive locations. “These crowdsourcing activities help us dive into the unknown and extract the unexpected,” Lin and his colleagues write. “However, beyond that they present a fundamental new construct for how we, as a digitally constructed society, interact with information.”