The largest pre-Columbian Site north of Mexico, Cahokia Mounds covered about 4000 acres and included 120 earthen mounds. Its peak population was by 10 – 20,000 people between AD 1050-1200. The State of Illinois, United States, now protects 2200 acres of the central portion of the site and 70 of the 80 remaining mounds. The site was named a U.S. National Historic Landmark in 1965, and in 1982, the United Nations Educational, Scientific, and Cultural Organization designated Cahokia Mounds a World Heritage Site for its significance in the prehistory of North America.
This image is an artist’s interpretation of what the central precinct of the site may have looked like during its zenith at about AD 1150. The view is of the Grand Plaza, looking north between the Twin Mounds, towards Monks Mound in the distance.