Ohio - Area of significance: Architecture
| McFarland, James, House |
| McGraw House |
| McIntire Terrace Historic District |
| McKay, Moses, House |
| McKee-Pumphrey House |
| McKelvey-Higbee Co. Buildings |
| McKenster-Groff House |
| McKever, Lewis, Farmhouse |
| McKinley Memorial |
| McKinley Park Apartments |
| McKinley School |
| McKinley School |
| McKinley School |
| McKinley Terrace |
| McKisson, Robert, House |
| McKitrick, Dr., House |
| McKitrick, Dr., Office |
| McLain-Gillmer House |
| McMillan, Reuben, Free Library |
| McNamar-McLure-Miller Residence |
| McPherson Town Historic District |
| McWilliams, Matthew, House |
| Mead House |
| Mead-Zimmerman House |
| Mechanics Building and Loan Company |
| Mechanicsburg Baptist Church |
| Mechanicsburg Commercial Historic District |
| Medfair Heights Apartment Historic District |
| Medical Centre Building |
| Medina County Courthouse |
| Medina Masonic Temple and Medina Theater |
| Medina Public Square Historic District |
| Meeker, Forrest, House and Farm |
| Meek, J.F., Buildings |
| Meigs County Fairgrounds, Grandstand and Racetrack |
| Meister Apartments, The |
| Melbourne Flats |
| Melville-Milne, William Gordon, House |
| Memorial Hall |
| Memorial Hall |
| Mendon Town Hall |
| Mentor Avenue District |
| Mentor Village Hall |
| Mentor Village School |
| Mentzer-Sorrick Farm |
| Mercantile Library Building |
| Mercer Log House |
| Merriman, Wells E., House |
| Merryman, Dr. James, House |
| Mertz, John, House |
| Merwin, George, House |
| Mesopotamia Village District |
| Metcalf, Rev. Harlan, House |
| Methodist Church, Old |
| Methodist Church Parsonage |
| Methodist Episcopal Church |
| Methodist Episcopal Church |
| Methodist Episcopal Church of Painesville, The |
| Methodist Parsonage, Old |
| Metropolitan Block |
| Meyer House |
| Meyers, Capt., House |
| Miami County Courthouse and Power Station |
| Miami-Erie Canal Site Historic District |
| Miami Monthly Meeting Historic District |
| Miami Street Grade School |
| Michaels Farm |
| Middle Bass Club Historic District |
| Middleport Public Library |
| Middle Sandy Presbyterian Church |
| Midtown Historic District |
| Milan Historic District |
| Miles, Enos, House |
| Miles Park Historic District |
| Mill Creek Park Historic District |
| Mill Creek Park Suspension Bridge |
| Mill & Dunn Historic District |
| Millen-Schmidt House |
| Miller-Bissell Farmstead |
| Miller Block |
| Miller, Charles A., House |
| Miller, Daniel, House |
| Miller, Daniel, House |
| Miller, Frederick A., House-Broad Gables |
| Miller, Harvey, Residence |
| Miller, J.F., House |
| Miller, John, House |
| Miller-Knight House |
| Miller-Leuser Log House |
| Miller, Lewis, House |
| Millersburg Historic District |
| Miller, Thomas, House |
| Mill Hollow House, The |
| Milligan, Cuthbert, House |
| Mills' Row |
| Mill Worker House No. 1 |
| Mill Worker House No. 3 |
| Mill Worker House No. 4 |
| Mill Worker House No. 5 |
| Minch, Capt., House |
Data from United States Park Service and Wikidata
