Prairie Creek Site in southwestern Indiana, north of Washington along Prairie Creek, emerged as a major archaeological discovery after mastodon bones were found eroding from the creek bank in 1972. Excavations showed the site was deeply stratified, with fifteen distinct layers of sand, silt, and clay created by repeated creek deposits. Finds included stone tools, burned wood, coal, animal bones, a bone fishhook, and remains of extinct animals such as Mylohyus and Castoroides, as well as an unusually far-north armadillo shell. Although some materials had been mixed by erosion and redeposition, later work confirmed a Paleoindian component, making the site important for understanding early human presence, environmental change, and animal life in Indiana.