Huge ancient city found in the Amazon
A huge ancient city has been found in the Amazon, hidden for thousands of years by lush vegetation, BBC News reports.
The discovery changes what we know about the history of people living in the Amazon.
The houses and plazas in the Upano area in eastern Ecuador were connected by an astounding network of roads and canals.
The area lies in the shadow of a volcano that created rich local soils but also may have led to the destruction of the society.
While we knew about cities in the highlands of South America, like Machu Picchu in Peru, it was believed that people only lived nomadically or in tiny settlements in the Amazon.
"This is older than any other site we know in the Amazon. We have a Eurocentric view of civilisation, but this shows we have to change our idea about what is culture and civilisation," says Prof Stephen Rostain, director of investigation at the National Centre for Scientific Research in France, who led the research.
"It changes the way we see Amazonian cultures. Most people picture small groups, probably naked, living in huts and clearing land - this shows ancient people lived in complicated urban societies," says co-author Antoine Dorison.
The city was built around 2,500 years ago, and people lived there for up to 1,000 years, according to archaeologists.
It is difficult to accurately estimate how many people lived there at any one time, but scientists say it is certainly in the 10,000s if not 100,000s.
The archaeologists combined ground excavations with a survey of a 300 sq km (116 sq mile) area using laser sensors flown on a plane that could identify remains of the city beneath the dense plants and trees.