Fort Ancient is a historic site in Warren County. An Ohio Historical Society web site says "Fort Ancient features 18,000 feet of earthen walls built 2,000 years ago by American Indians who used the shoulder blades of deer, split elk antler, clam shell hoes and digging sticks to dig the dirt. They then carried the soil in baskets holding 35 to 40 pounds. Portions of these walls were used in conjunction with the sun and moon to provide a calendar system for these peoples. The site offers beautiful vistas along hiking trails as well as the remains of the prehistoric mounds for visitors to see."
The OHS says the museum focuses on 15,000 years of American Indian history in the Ohio Valley. Fort Ancient is seven miles southeast of Lebanon on Ohio 350.