Cahokia, the largest pre-Columbian city in North America north of Mexico. Flourishing around 1100 CE, Cahokia supported tens of thousands of people, built massive earthen mounds, and controlled extensive trade networks. Its society was deeply spiritual, highly hierarchical, and closely tied to environmental balance. Cahokia’s decline—likely caused by climate stress, resource depletion, and social tension—led to its abandonment centuries before European arrival. Long misunderstood, Cahokia now stands as a testament to Indigenous ingenuity and the vulnerability of even the greatest cities.