Wolf Plains in southeastern Ohio is a major Late Adena archaeological complex on a broad terrace in the Hocking River valley, consisting of thirty earthworks with conical mounds and circular enclosures. Its prominence was recognized early in American archaeology through its inclusion in the eighteen forty-eight Ancient Monuments of the Mississippi Valley, helping establish it as one of Ohio's significant earthwork landscapes despite flaws in the earliest recorded plan. Listed on the National Register of Historic Places in nineteen seventy-four, it still retained twenty-five contributing earthworks. Preservation remains difficult because much of the site is privately owned and the surviving features face ongoing threats from development and accidental damage.