EXPLORE · ANCIENT SITES
Ancient Sites in Illinois
Cahokia Mounds, 8 miles east of St. Louis, is one of the most underappreciated ancient sites in North America. At its peak around 1050-1100 AD, this was the largest city north of Mexico — an estimated 10,000 to 20,000 people spread across six square miles of Mississippi River floodplain. Monks Mound, the central platform, has a larger base footprint than the Great Pyramid of Giza and rises 100 feet. You can climb it. You can see the St. Louis arch from the top. The fact that this UNESCO World Heritage Site is known primarily to archaeologists and not to the millions of people within a day's drive represents one of the great gaps in American cultural awareness.
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Cahokia Mounds State Historic Site
The largest pre-Columbian city north of Mexico — at its peak around 1050-1100 AD, Cahokia was home to an estimated 10,000-20,000 people spread across 6 square miles of the Mississippi River floodplain. Monks Mound, the central pyramid, is larger at its base than the Great Pyramid of Giza and rises 100 feet — you can climb it. UNESCO World Heritage Site. Over 80 mounds remain on 2,200 acres. Free (suggested donation). Outstanding interpretive center. One of the most underappreciated archaeological sites in the world — most Americans have never heard of it. Just 8 miles from downtown St. Louis, near Collinsville, IL.
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Petroglyphs, ruins, mounds, dinosaur tracks — interactive map with filters, all on public land.
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