A site of long occupation in west-central Illinois, known as one of the first multidisciplinary endeavors of new archaeology; the findings serve as a benchmark for defining the Archaic period in the Midwest. The site is unusual for its long stratigraphic sequence of Archaic and Woodland settlements, dating from c 8700 bp to 1000 AD. Hunter-gathers and, later, farmers, settled at this location on the Illinois River to exploit the fertile river bottom. The site served variously as a workshop for stone tools, a deer-butchering camp, and possibly as the site for one of the earliest villages in North America. Stoneground adzes, manos and metates are dated c 6400 BC. In later levels, there is evidence of increased hunting efficiency (the replacement of the atlatl by the bow and arrow) and of agriculture (squash and pumpkin), and possibly Mississippian association. The site also contributed to the methodology of excavation, including approaches to deeply buried sites, and the use of flotation as a technique.