This park contains one of Wisconsin's most important archaeological sites. It showcases an ancient Middle-Mississippian village and ceremonial complex that thrived between A.D. 1000 and 1300. Archaeologists theorize that the occupants may have cultural traditions in common with Cahokia, a large Middle-Mississippian settlement near East St. Louis, Illinois. The people who settled Aztalan built large, flat-topped pyramidal mounds and a stockade around their village. They hunted, fished, and farmed on the floodplain of the Crawfish River. Portions of the stockade and two mounds have been reconstructed in the park.