Topic - Cahokia

(11 MS 2) is located on the site of an ancient Native American city (c. 600–1400 CE) situated directly across the Mississippi River from modern St. Louis, Missouri. This historic park lies in southern Illinois between East St. Louis and Collinsville.The park covers 2,200 acres (890 ha), or about 3.5 square miles, and contains about 80 mounds, but the ancient city was actually much larger. In its heyday, Cahokia covered about six square miles and included about 120 human-made earthen mounds in a wide range of sizes, shapes, and functions. - Source: Wikipedia