The earliest portion of Towosahgy State Historic Site is in the southern half, where a Late Woodland village once stood. Wilkie dates this component to about 400 to 700 CE.
Later the site was fortified and built up as a Mississippian site with seven earthwork mounds, most surrounding a central plaza. During this time, the site was surrounded by a palisade wall of vertical logs and a moat. Like other Mississippian mound centers, Towosahgy also had a borrow pit, where earth was removed to create the mounds. The largest remaining mound is Mound 2, also known as the "temple mound". Excavations on this part of the site were conducted in 1989 by James Price. The site was abandoned during the late fourteenth century for unknown reasons, as were many similar Mississippian sites in the region.
^John W. Cottier and Michael D. Southard (1977). An Introduction to the Archaeology of Towosahgy State Archaeological Site. Missouri Archaeologist. pp. 230–268.
^ abJames E. Price and Cynthia R. Price (1990). Archaeological Investigations in Three Areas of the Towosahgy State Historic Site, 23MI2, Mississippi County, Missouri, 1989. Columbia, Mo.: University of Missouri-Columbia. OCLC68738170.