Cahokia Mounds State Historic Site

A thousand years ago the biggest city north of Mexico stood not far from present-day St Louis. Cahokia flourished in the Mississippian era, spreading over nearly 1,600 hectares with some 120 earthen mounds; at its peak between 1050 and 1150 perhaps 10,000 to 20,000 people lived beneath Monks Mound, a 30-metre platform that remains the largest prehistoric earthen monument in the Americas. UNESCO inscribed Cahokia Mounds in 1982.