Which UNESCO World Heritage Site in the United States preserves the remains of the pre-Columbian city of Cahokia?

The UNESCO World Heritage Site in the United States preserving the pre-Columbian city of Cahokia is Cahokia Mounds State Historic Site.

Cahokia developed near present-day Collinsville, Illinois, across the Mississippi River from St. Louis. It was the largest urban centre of the Mississippian culture and flourished roughly from 900 to 1350 CE. At its height, the settlement supported a large population and an extensive network of communities.

The site contains earthen pyramids, plazas, residences, and ceremonial or political spaces. Monks Mound is the largest earthwork at Cahokia and the largest prehistoric earthen structure in the Americas north of Mesoamerica. Its construction required the organized movement of enormous quantities of soil.

UNESCO inscribed Cahokia Mounds in 1982. The site is sometimes described simply as a group of mounds, but it was a complex city with social ranking, trade, ritual life, and planned spaces. Cahokia’s decline followed several centuries of expansion and remains an important subject in North American archaeology.