Ohio - Area of significance: Politics/Government
| Krumm House |
| Langston, John Mercer, House |
| Laurel Homes Historic District |
| Lawrence, William, House |
| Leipsic City Hall |
| Levering Hall |
| Lisbon Historic District |
| Longwood Manor |
| Looker, Othniel, House |
| Lorain Fire Station No. 1 |
| Lundy, Benjamin, House |
| Mahoning Avenue Historic District |
| Main Street Historic District |
| Mansfield, Judge, House |
| Marietta Historic District |
| Martindale, Samuel, House |
| Masonic Temple |
| May 4, 1970, Kent State Shootings Site |
| McCracken-Scott House |
| McIntire Terrace Historic District |
| McKinley Memorial |
| McKinley, William, Tomb |
| McSweeney, John, House |
| Medill, William, House |
| Medina County Courthouse |
| Mendon Town Hall |
| Mentor Avenue District |
| Mentor Village Hall |
| Monroe County Courthouse |
| Monroe Township Hall-Opera House |
| Montgomery County Courthouse |
| Mooney, William C., House |
| Moore, Leonard M., House |
| Morgan Township House |
| Mother Thompson House |
| Mount Auburn Historic District |
| Munson, Judge Albert, House |
| National Road |
| Newman, William, House |
| New Market Township Community House |
| Newton, Judge Eben, House |
| Northfield Town Hall |
| North Olmsted Town Hall |
| Ohio Company Land Office |
| Ohio Statehouse |
| Ohio State Office Building |
| Ohio State Reformatory |
| Old City Hall |
| Old District 10 Schoolhouse |
| Old Euclid District 4 Schoolhouse |
| Old Governor's Mansion |
| Old Lawrence County Jail |
| Old Mahoning County Courthouse |
| Old Post Office And Federal Building |
| Old US Post Office |
| Old Wayne County Jail |
| Overfield Tavern |
| Paige, David R., House |
| Painesville City Hall |
| Pendleton, George Hunt, House |
| Perry County Courthouse and Jail |
| Piketon Historic District |
| Pomerene House |
| Port Washington Town Hall |
| Pringle-Patric House |
| Promont |
| Prospect Place |
| Putnam Historic District |
| Reid, Whitelaw, House |
| Rider, Adam, House |
| Rinehart, Hugh T., House |
| Rombach Place |
| Root, William H., House |
| Ross-Gowdy House |
| Round Hill |
| Saxton House |
| Shack, The |
| Shandy Hall |
| Sherman, John, Memorial Gateway |
| Sloane, Rush R., House |
| Smart Building |
| Sollars Farmstead |
| Somerset Historic District |
| South Main Street District |
| Springdale |
| Stark County Courthouse and Annex |
| Strongsville Town Hall |
| Studabaker-Scott House and Beehive School |
| Tallmadge Town Square Historic District |
| Tannehill, Capt. James Boggs, House |
| Tawawa Chimney Corner |
| Taylor, Colonel Joseph, House |
| The Ridge |
| Town Center District |
| Townes, Clayton, House |
| Trailsend |
| United States Post Office |
| Upton, Harriet Taylor, House |
| Versailles Town Hall and Wayne Township House |
| Voice of America Bethany Relay Station |
Data from United States Park Service and Wikidata
