Archaeologists discover ancient metropolis under St Louis

IT'S MUCH LARGER THAN THEY EVER KNEW OR EXPECTED:

The lost city of Cahokia: Archaeologists uncover Native Americans' sprawling metropolis under St Louis: 

... At its peak between 1100 and 1200, the city covered nearly six square miles and boasted a population of 100,000 people.   

... Residents built more than 120 earthen mounds. A total of 68 are preserved within the site, with the largest central one called Monks Mound. 

... At 1,000 feet long, 800 feet wide and 100 feet tall, an estimated 22 million cubic feet of earth was used to build it.

RTWT - AND LOOK AT THE VIDEO AND PHOTOS AND DIAGRAMS!