A map of Ohio Hopewell sites. Southern Ohio is the locale of the most abundant and richest Hopewell sites. The majority are found along the Miami, Scioto, and Muskingum rivers and range in date from 100 BC to 550 AD. After that no more lowland centers were built; instead hilltops were fortified (colored dots locate three major examples). The McGraw site was excavated by the author (Olaf H. Prufer).