Armco Park Mound II is a registered historic site near Otterbein, Ohio, United States, listed in the National Register on 29 May 1975. Historic uses Graves/burials See also List of Registered Historic Places in Warren County, Ohio* List of burial mounds in the United States References National Register of Historic Places in Warren County, Ohio Archaeological sites on the National Register of Historic Places in Ohio Geography of Warren County, Ohio Mounds in Ohio