Illinois State Archaeologist Tim Pauketat led a tour of Cahokia Mounds on Sept. 19 for a group of University of Illinois alumni. This special event was organized by the Illinois Alumni Association and the Prairie Research Institute.
Cahokia appeared around 1050 A.D. and lasted for about 150 years. At the peak of this spiritual and political center, three urban "precincts"—Cahokia, St. Louis, and East St. Louis—covered 6–8 square miles. The population was 15,000–20,000, with between 20,000 and 50,000 more farmers living outside the city.