The US National Academy of Sciences has published the results of a survey performed in April 2012 of the forests of Cambodia, which uncovered a monumental, intricate landscape of low-density urban sprawl connected to ancient ruins of Angkor Wat that dates back to more than 700 years, invalidating archaeologists’ current understandings of pre-industrial urbanism.

Until now, scholars have based their thoughts of medieval cities around the world on European cities. This study has revealed a colossal low-density urban system with working citadels and vast infrastructures in Cambodia. Lara Dunston of The Guardian wrote that the “high-tech survey of Khmer Empire sites has rocked the archaeological world and captured travelers’ imaginations.”

The densely populated, sophisticated landscape system consists of and links Angkor cities such as Angkor Wat, Angkor Thom, and Bayon, along with seldom visited medieval city ruins of Phnom Kulen, Beng Mealea and Koh Ker, over 62 miles away. Koh Ker, 75 miles from Siem Reap, and Beng Mealea, 32 miles away, were thought of as isolated structures, but the study has revealed that they were actually large outlying service centers for Angkor.