For decades, the Amazon was seen as an untouched wilderness where large civilizations could never have survived. But in the 1990s, French archaeologist Stéphen Rostain began challenging that idea. Working in Ecuador’s Upano Valley, he spent years digging by hand through the dense 'green wall' of trees. He found individual earthen mounds, pottery, and ancient hearths—clear proof that people had lived there long before Europeans arrived. Yet his discoveries were met with skepticism. Rostain could prove a few people had lived there, but without a view from above, he couldn’t see the true scale of what was hidden. He was standing on the edge of a lost world, but the jungle kept its biggest secret.
Lost Cities of the Amazon
LIDAR found over 6,000 ancient platforms hidden beneath Ecuador's rainforest canopy, revealing a 2,500-year-old urban network.
The Green Wall
Frequently Asked Questions
How did scientists find cities hidden in the Amazon rainforest?
Researchers used an aerial technology called LIDAR, which fires laser pulses from a plane. A small percentage of these lasers penetrate the forest canopy to map the ground below, creating a 3D model of the bare earth and revealing structures hidden by the trees.
How old are the lost cities of the Upano Valley?
Radiocarbon dating confirmed the sites were first occupied around 500 BCE and inhabited until between 300 and 600 CE. This makes the civilization over 1,000 years older than other known complex urban societies in the Amazon.
How many people lived in these ancient Amazonian cities?
Archaeologists estimate that at its peak, the population in the valley was between 10,000 and 30,000 people. This population density is comparable to that of Roman-era London.
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