WASHINGTON (Reuters) - Brazil's northern Amazon region, once thought to have been pristine until modern development began encroaching, actually hosted sophisticated networks of towns and villages hundreds of years ago, researchers said on Thursday.

Archeological evidence and satellite images show the area was densely settled long before Columbus and European settlers arrived, with towns featuring plazas, roads up to 150 feet wide, deep moats and bridges, the researchers found.

The report, published in the journal Science, suggests a society that was advanced and complex, and that found alternative ways to use the Amazon forest without destroying it.

Nineteen evenly spaced villages were linked by straight roads, and the cluster could have supported between 2,500 and 5,000 people, said the researchers, led by Michael Heckenberger of the University of Florida.

Very cool shit. The highways they built were on the order of 150' wide, which definately throws them into the catagory of superhighways. What's making me smile about this one is that no matter how much we think we know about our planet and its social evolution, it still manages to surprise. Nice job, ancient Amazonians.