Higher Ground: America's Mound Builders · Episode 4 of 7 · 47 min
Cahokia: The Largest Ancient City in North America
Around 1050 CE, on the Mississippi floodplain across from modern St. Louis, Native Americans built the largest city north of Mexico: Cahokia, with 15,000 to 20,000 people, roughly 120 mounds, a 50-acre grand plaza and the 100-foot Monks Mound. They built it on purpose in a flood basin, during a rare centuries-long lull in the river's biggest floods.
Who's who
- Samuel Munoz+1 more episodeGeoscientist whose 2015 sediment-core study charted the flood lull
Where it happens
- Cahokia, American Bottom, IllinoisLargest ancient city in North America north of Mexico
- Monks Mound, Cahokia, Illinois+1 more episodeAbout 100 feet tall, with a base comparable to the Great Pyramid
- St. Louis, Missouri+2 more episodesCity across the river from Cahokia
Timeline
- c. 600 CEBig Mississippi floods diminish and people move onto the floodplain.
- c. 900 CEMaize agriculture takes hold and population climbs sharply.
- c. 1050 CECahokia is rapidly reorganized into a planned city.
- c. 1175-1200 CEA two-mile palisade is raised around the central precinct.
- c. 1200 CEA major flood appears in sediment cores as decline begins.
- c. 1350-1400 CECahokia is effectively deserted.
Still debated
Cahokia's population estimates range from 6,000 to 40,000 or more, and the mound count is a floor rather than a firm total. Why the city rose and why it fell remain debated.