GUATEMALA CITY-Experts using an aerial high-tech laser scanner have discovered thousands of ancient Maya structures hidden under the thick jungle of northern Guatemala, officials said Thursday.

Some 60,000 structures were found over the past two years in a scan of a region in the northern department of El Peten, which borders Mexico and Belize, said Marcello Canuto, one of the project’s top investigators.

These findings are a “revolution in Maya archeology,” Canuto said.

The new discoveries in this Central American country include urban centers with sidewalks, homes, terraces, ceremonial centers, irrigation canals and fortifications, said Canuto, an archaeologist at Tulane University in the United States. Among the finds was a 30-meter high pyramid that had been earlier identified as a natural hill in Tikal, Guatemala’s premier archaeological site. Also discovered in Tikal: a series of pits and a 14 kilometer-long wall.

The Maya civilization reached its height in what is present-day southern Mexico, Guatemala, and parts of Belize, El Salvador and Honduras between 250 and 950 CE. Researchers now believe that the Maya had a population of 10 million, which is “much higher” than previous estimates, Canuto said.

The project relied on a remote sensing method known as LiDAR (Light Detection and Ranging). Aircraft with a LiDAR scanner produced three-dimensional maps of the surface by using light in the form of pulsed laser linked to a GPS system. The technology helped researchers discover sites much faster than using traditional archeological methods.

“Now it is no longer necessary to cut through the jungle to see what’s under it,” said Canuto. Details of the research will appear in a documentary to air on February 11 on the National Geographic channel, said Minister of Culture and Sports Jose Luis Chea.