Ancient Builders of the Amazon

According to new mapping technology, if Spanish conquistadors had invaded the Amazon 200 years earlier, they would have found a sophisticated culture in cities connected by canals and raised causeways, rather than a dense, sparsely populated jungle.  Using data from airborne infrared beams, scientists can now digitally deforest the Amazon, revealing vast urban settlements with 70'-high conical pyramids.  Who built them?  How did people live and worship here?  And why did they disappear?  Share the excitement as researchers race to find answers before the wilderness disappears!  1 hour on 1 disc. SDH