Author: David Gramm. Published by Vintage Departures Division of Random House, 2010. The first explorers to travel the length of the AMazon reported a populous region, with many large and busy cities on its banks, among other wonders.
"So where are they?" wondered intrepid explorer Col. Percy Fawcett, from 1906 through 1914, and again in the 1920s. He disappeared into the jungle and many expeditions were sent to find him or news of him in the years that followed.
In modern times, teams of archeologists have figured out that these mysterious regions were heavily populated and had large impressive cities, with sophisticated agriculture ...permaculture ... that was capable of supporting huge populations, perhaps wiped out by pandemics of disease introduced by the Spaniards and Portuguese.
Several American Universities and Brazilian archaelogists are very busy sorting it all out. Leading the field, Mike Heckenberger of the University of Florida.
So check out the book, the true story of a great explorer, Col Percy H. Fawcett.