At its peak around 1100 CE, Cahokia held perhaps 20,000 people. Monks Mound, its central platform, contains 622,000 cubic metres of hand-carried soil — the largest earthwork in the Americas. The city was planned on a precise grid around plazas, with 'Woodhenge', a circle of red cedar posts, marking the solstices and equinoxes against the mound's silhouette.
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Notable facts
- Monks Mound's base is larger in footprint than the Great Pyramid of Giza.
- Woodhenge was built as five successive circles, each with twelve more posts than the last.
- Mound 72 held a burial on a platform of 20,000 shell beads arranged as a falcon.
Through the theories
How each theory reads Cahokia Mounds. Follow a theory to see its verdict and every other site it claims.
Sky AlignmentsEstablished science
Woodhenge's post circle is a functioning solar calendar aligned on the equinox sunrise over Monks Mound.
Earth GridNo measurable evidence
Its river-confluence siting features in 'telluric current' theories of mound placement.
