Ohio - Significance region: Local
| Athens State Hospital Cow Barn |
| Athletic Club of Columbus |
| Atlas National Bank Building |
| Atwater Congregational Church |
| Audubon School |
| Augspurger, Frederick, Farm |
| Augspurger Grist Mill |
| Augspurger, John, Farm No. 1 |
| Augspurger, John, Farm No. 2 |
| Augspurger Paper Company Rowhouse #1 |
| Augspurger Paper Company Rowhouse #2 |
| Augspurger, Samuel, Farm |
| Augspurger, Samuel, House |
| Augspurger Schoolhouse |
| Aullwood House and Garden |
| Ault-Weygandt Farm |
| Aurora Center Historic District |
| Aurora Train Station |
| Ausenbaugh-McElhenny House |
| Austin, Eliphalet, House |
| Austin Hall |
| Austin-Magie Farm and Mill District |
| Austintown Log House |
| Avery, Carlos, House |
| Avon Isle |
| Bagby-Hossler House |
| Bailey-Thompson House |
| Bair, Jacob H., House |
| Baker Brothers Wholesale Grocery |
| Baker, John, Tavern |
| Baker Motor Vehicle Company Building |
| Baker, O. T., House |
| Baldwin, Joseph W., House |
| Baldwin Piano Company Building |
| Baldwin-Wallace College North Campus Historic District |
| Baldwin-Wallace College South Campus Historic District |
| Ballard Road Covered Bridge |
| Baltimore & Ohio Railroad Terminal |
| Bank Block Building |
| Bank Of Xenia |
| Bantam Ridge School |
| Bappert, Joseph and Cecilia, House |
| Baptist Parsonage, Old |
| Barber, O. C., Barn No. 1 |
| Barber Shop |
| Barberton Downtown Historic District |
| Barber-Whitticar House |
| Barder, Byron R., House |
| Barker, Col. Joseph, House |
| Barker, Judge Joseph, Jr., House |
| Barker School |
| Barker Village Site |
| Barker, William, Residence |
| Barkhurst Mill Covered Bridge |
| Barnesville Baltimore and Ohio Railroad Depot |
| Barnesville Historic District |
| Barnesville Petroglyph |
| Barnett-Criss House |
| Barney, Freeland T., House |
| Barnhardt-Bolenbaugh House |
| Barnhisel, Henry II, House |
| Barr Hotel |
| Barr House |
| Barr, Jacob H., House |
| Bartlett, Joseph and Rachel, House |
| Batavia House |
| Bates Building |
| Bates-Cockrem House |
| Bath Township Consolidated School |
| Bath Township Hall |
| Bath Township School |
| Battle of Berlin Heights Engagement Site |
| Bauer Apartments |
| Baum, Howard, Site (33RO270) |
| Bavarian Brewery |
| Baxter, James, House |
| Baxtine House |
| Bay View Hospital |
| Bazore Mill |
| Beam Farm Woodland Archeological District |
| Beasley Building |
| Beatty Glass Company |
| Beatty, Louis, House |
| Beatty-Moore House |
| Becker, Francis, House |
| Becker House |
| Becker Lumber and Manufacturing Company |
| Beckett-Manrod House |
| Bedford Baptist Church |
| Bedford Historic District |
| Beebe, Horace Y., House |
| Beech Avenue Houses |
| Beecher, Lucas, House |
| Beehive School |
| Beer, Judge Thomas, House |
| Beers, Samuel, House |
| Beery, Dr. L. W., House |
| Beir, Anna, House |
| Bell Covered Bridge |
| Bell, C.S., Foundry and Showroom |
Data from United States Park Service and Wikidata
