Cahokia's largest mound is the biggest earthwork built in pre-Columbian North America, and one burial found within the site's mound complex points to organised human sacrifice on a scale rarely documented so clearly at any other Indigenous North American site.
The largest mound north of Mexico
Monks Mound, the central earthwork at Cahokia, covers a footprint larger than the base of the Great Pyramid of Giza and was built up in stages using an enormous volume of hand-carried earth, supporting what was likely an elite residence or ceremonial structure at its summit, a scale of engineered construction unmatched at any other known site north of Mesoamerica.
A calendar made of posts
Woodhenge, a series of large wooden post circles rebuilt several times at different diameters, functioned as a solar calendar, with specific posts aligned to mark sunrise positions at the solstices and equinoxes, evidence of precise astronomical observation built directly into the city's ceremonial landscape rather than left to informal seasonal tracking.
What Mound 72 held
Excavation of Mound 72 uncovered a man buried on a bed of thousands of shell beads, accompanied by the remains of numerous other individuals, including a group of young women, interpreted by archaeologists as retainer sacrifices accompanying an elite burial, among the clearest documented evidence of organised human sacrifice at any pre-Columbian site in eastern North America.