Cahokia Mounds is the largest archaeological site related to the Mississippian culture, which developed advanced societies in the central and eastern present-day United States. It is designated a National Historic Landmark and listed on the National Register of Historic Places. UNESCO designated the Cahokia Mounds State Historic Site as a World Heritage Site. It is the only site in Illinois and among only twenty-one cultural World Heritage Sites in the United States. Cahokia Mounds was designated a National Historic Landmark in 1964, and listed on the National Register of Historic Places in 1966.

It is among only twenty-one cultural World Heritage Sites in the United States.