Native American city, one of the largest in pre-Columbian North America. Cahokia lies near where present-day St. Louis is, and was home to around 25,000 people at the peak of its civilization in the 12th century. By all archaeological accounts, Cahokia had all the benefits of a modern city - a specialized labor force, organized government, public construction projects, and a trade network that stretched all the way to the Atlantic. It also had some of the problems we see today - over-population, smog, and deforestation. By 1400, the city had been completely abandoned. The descendants are thought by archaeologists to have assimilated into other tribes.

An agrarian society, the people of Cahokia survived mainly by harvesting corn. Despite being unable to read or write, the Cahokians constructed "Woodhenge", a wooden astronomical calendar that appears to be similar in function to Stonehenge. The Cahokians also built Mayan-like pyramidal mounds, including the 22 million cubic foot Monks Mound, and surrounded their city with a twenty-foot wall of wood constructed from over 20,000 trees.

The city was almost completely lost. French explorers who were the first to visit the region met only small groups of Illini. Consequently, most of Cahokia was built on top of. The remainder of the city is preserved at the Cahokia Mounds State Historic Site in Illinois.