It is the second largest wine appellation of origin in the United States (only the Upper Mississippi Valley is larger) with 16,640,000 acres (26,000 sq mi) (67,300 km2) in portions of the states of Indiana, Kentucky, Ohio and West Virginia.
The area is mostly planted with hybrid grapes like Baco noir, Marechal Foch, Seyval blanc and Vidal.
The river formed on a piecemeal basis beginning between 2.5 and 3 million years ago.
The earliest Ice Ages occurred at this time and dammed portions of north flowing rivers.
The vineyard soils of the Ohio River Valley are diverse, being on the boundary between glaciated and non-glaciated.