Researchers have found more than 60,000 hidden Maya ruins in Guatemala in a major archaeological breakthrough.
Laser technology was used to survey digitally beneath the forest canopy, revealing houses, palaces, elevated highways, and defensive fortifications.
The landscape, near already-known Maya cities, is thought to have been home to millions more people than other research had previously suggested.
The researchers mapped over 810 square miles (2,100 sq km) in northern Peten.
Archaeologists believe the cutting-edge technology will change the way the world will see the Maya civilisation.
Results from the research using Lidar technology, which is short for "light detection and ranging", suggest that Central America supported an advanced civilisation more akin to sophisticated cultures like ancient Greece or China.
How does Lidar work?
Described as "magic" by some archaeologists, Lidar unveils archaeological finds almost invisible to the naked eye, especially in the tropics.
It is a sophisticated remote sensing technology that uses laser light to densely sample the surface of the earth
Millions of laser pulses every four seconds are beamed at the ground from a plane or helicopter
The wavelengths are measured as they bounce back, which is not unlike how bats use sonar to hunt
The highly accurate measurements are then used to produce a detailed three-dimensional image of the ground surface topography
In recent years Lidar technology has also been used to reveal previously hidden cities near the iconic ancient temple of Angkor Wat in Cambodia.
Maya civilisation, at its peak some 1,500 years ago, covered an area about twice the size of medieval England, with an estimated population of around five million
Most of the 60,000 newly identified structures are thought to be stone platforms that would have supported the average pole-and-thatch Maya home.
The archaeologists were struck by the "incredible defensive features", which included walls, fortresses and moats.
They showed that the Maya invested more resources into defending themselves than previously thought, Mr Garrison said.
One of the hidden finds is a seven-storey pyramid so covered in vegetation that it practically melts into the jungle.
Another discovery that surprised archaeologists was the complex network of causeways linking all the Maya cities in the area. The raised highways, allowing easy passage even during rainy seasons, were wide enough to suggest they were heavily trafficked and used for trade.
The Lidar survey was the first part of a three-year project led by a Guatemalan organisation that promotes cultural heritage preservation. It will eventually map more than 5,000 sq miles (14,000 sq km) of Guatemala's lowlands.
The project's discoveries will feature in a Channel 4 programme called Lost Cities of the Maya: Revealed, airing in the UK on Sunday 11 February at 20:00 GMT, reports BBC.