Built from an estimated 22 million cubic feet of earth and standing about 100 feet high, Monks Mound is the tallest structure at the Cahokia Mounds State Historic Site.

This American Indian metropolis was mysteriously abandoned. Archaeologists want to know why.

Cahokia was a robust economic and cultural center for the Mississippian people. They built hundreds of massive mounds but suddenly left the city in the 1300s.

Built from an estimated 22 million cubic feet of earth and standing about 100 feet high, Monks Mound is the tallest structure at the Cahokia Mounds State Historic Site.
Ira Block/National Geographic Image Collection
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