Mills County Iowa has 6 places on the National Register of Historic Places including 1 place of National significance and 3 places of Statewide significance. Significant places include West Oak Forest Earthlodge Site, Nishnabotna River Bridge, Plattsmouth Bridge and West Oak Forest Earthlodge Site and Pony Creek Park.
Prehistoric cultural affiliation(s) include Native American, Glenwood Culture, Central Plains Tradition and Nebraska Phase dating back to 1000.
Some of the country's most noteable architects helped create the Mills County places including Iowa State Highway Commission, Omaha Structural Steel Works and McCormack Construct Inland Steel Co. Prominent architectural styles found in Mills Country are .
