© Google EarthOne of the massive earthworks discovered around Acre.
"I said, 'Wow, what am I seeing?'" said Alceu Ranzi, a geographer and palaeontologist with the Federal University in the Brazilian state of Acre. "This is not natural."
What he saw that afternoon in 1999 was a giant, geometrically precise circle carved in the earth. Nearly invisible from the ground, the earthwork had only recently emerged when farmers cleared a tract of forest. The huge structures suggested the area may have been home to many more people than anyone previously believed.
"It's something new that no one expected," Ranzi said. "No one expected that a discovery of this level still could have happened in that region."
Ranzi recruited a team of archaeologists from Brazil and Finland and began searching for more of these earthworks, which he calls geoglyphs.
Their work on the ground in this Brazilian border state has recently received an unlikely boost from space. New Google Earth images this year revealed even more of the formations. The scientists now say they've tallied 300 massive shapes - circles, squares, rectangles - scattered across 3,900 square miles.
Ranzi said the size and breadth of the discovery reveals that, some 1,000 years ago, the region was home to a large, complex society. The find has expanded a rapidly growing body of archaeological evidence suggesting that the Amazon - once thought to be largely wild in antiquity - was home to civilizations that may have rivalled those of the ancient West.
Very little has been done, up until now, to preserve these sites," Piccoli said. "And there's still so much left to discover.
Reader Comments
to our Newsletter