One of the largest Mississippian sites is Kincaid Mounds State Historic Site, located in Massac and Polk counties in southern Illinois. It is southeast of Cahokia, located in the floodplain of the Ohio River. With a total of 19 mounds at the complex, it is considered the fifth-largest Mississippian site in terms of the number of monuments. It is believed to have been a chiefdom, as an elite burial mound was among those found. The site is designated as a National Historic Landmark.