Pennsylvania - Criteria: A (event)
| Miller, David H., Tobacco Warehouse |
| Miller Hall |
| Millersburg Ferry |
| Millersburg Passenger Rail Station |
| Miller's Store |
| Milleysack, J. B. Cigar Factory |
| Millheim Historic District |
| Millionaire's Row Historic District |
| Millmont Farm |
| Millmont Red Bridge |
| Mill Rift Hall |
| Mill Tract Farm |
| Milton Armory |
| Milton Freight Station |
| Milton Historic District |
| Minersville Coke Ovens |
| Minersville Historic District |
| Mingo Creek Presbyterian Church and Churchyard |
| Mishler Theatre |
| Mitchell, James, House |
| Modern Tool Company |
| Moland House |
| Monongahela Incline |
| Monroe County Courthouse |
| Monroe Furnace |
| Monroe Tavern |
| Monterey Historic District |
| Monte Vista |
| Montgomery Ward Building |
| Mooncrest Historic District |
| Moore Hall |
| Mooresburg School |
| Moravian Pottery and Tile Works |
| Moravian Sun Inn |
| Morgan, Edward, Log House |
| Morgantown Historic District |
| Morris-Hair Tavern |
| Morse, Samuel F. B., School |
| Mortonville Hotel |
| Moselem Farms Mill |
| Mosier, Dr. J. R., Office |
| Mother Bethel A.M.E. Church |
| Mountain Springs Hotel |
| Mount Hope Estate |
| Mount Pleasant Armory |
| Mount Pleasant Historic District |
| Mount Pleasant Historic District |
| Mount St. Peter Roman Catholic Church |
| Mount Union Historic District |
| Mount Vernon Furnace |
| Moxham Historic District |
| Mt. Lebanon Historic District |
| Mt. Pleasant Covered Bridge |
| Muddy Creek Bridge, Maryland and Pennsylvania Railroad |
| Muddy Creek Forks Historic District |
| Muhr, Simon, Work Training School |
| Mulford Building |
| Mumma, Samuel N., Tobacco Warehouse |
| Muncy Historic District |
| Municipal Building and Central Fire Station, 340 |
| Musical Fund Hall |
| Narbrook Park Historic District |
| Nathan's Department Store |
| National Transit Building |
| Nazareth Hall Tract |
| Nazareth Historic District |
| Nearpass House |
| Neff Round Barn |
| Neff's Mill Covered Bridge |
| Nesquehoning High School |
| Neuweiler Brewery |
| New Baltimore Bridge |
| New Castle Armory |
| New Century Clubhouse |
| New Century Guild |
| New Colonial Hotel |
| New Enterprise Public School |
| New Era Building |
| New Freedom Railroad Station, Northern Central Railway |
| New Geneva Historic District |
| New Germantown Covered Bridge |
| New Granada Theater |
| New Hamburg Historical Area |
| New Holland Machine Company |
| New Hope Village District |
| New Kensington Downtown Historic District |
| New Kensington Production Works Historic District |
| Newlin Mill Complex |
| Newlin Miller's House |
| Newlin, Nicholas, House |
| New Market |
| Newport Historic District |
| New Ringgold Gristmill |
| New Thomson House |
| Newtown Friends Meetinghouse and Cemetery |
| Newtown Historic District |
| Nicholson House and Inn |
| Ninth Street Bridge |
| Nissly-Stauffer Tobacco Warehouses |
| Nissly Swiss Chocolate Company |
Data from United States Park Service and Wikidata
