The discovery, which was revealed using lasers, sheds new light on the civilisation behind the world’s largest religious complex.
While the research has been going on for several years, the new findings uncover the sheer scale of the Khmer Empire’s urban sprawl and temple complexes.
The findings also reveal it was significantly bigger than was previously thought.
The research, drawing on airborne laser scanning technology known as lidar, was unveiled in full at the Royal Geographic Society in London overnight by Australian archaeologist Damian Evans.
“We always imagined that their great cities surrounded the monuments in antiquity,” Evans said.
“But now we can see them with incredible precision and detail, in some places for the very first time, but in most places where we already had a vague idea that cities must be there,” he added.
Angkor Wat, a UNESCO World Heritage site seen as among the most important in southeast Asia, is considered one of the ancient wonders of the world.
It was constructed from the early to mid 1100s by King Suryavarman II at the height of the Khmer Empire’s political and military power and was among the largest pre-industrial cities in the world.
But scholars had long believed there was far more to the empire than just the Angkor complex.