Pennsylvania - Area of significance: Architecture
| Michener, Nathan, House |
| Middishade Clothing Factory |
| Middlekauff, Jacob and Juliana, House |
| Middle Pickering Rural Historic District |
| Midtown Harrisburg Historic District |
| Mifflinburg Historic District |
| Mifflin County Courthouse |
| Mifflin Elementary School |
| Mifflin School |
| Mifflin, Thomas, School |
| Milanville Historic District |
| Miles-Humes House |
| Milford Historic District |
| Mill at Lobachsville |
| Mill Creek Historic District |
| Miller, Andrew S. and Elizabeth, House |
| Miller, Christian, House |
| Miller, David H., Tobacco Warehouse |
| Miller Hall |
| Miller, James, House |
| Millersburg Passenger Rail Station |
| Miller's House at Spring Mill |
| Miller's Store |
| Milleysack, J. B. Cigar Factory |
| Millheim Historic District |
| Millionaire's Row Historic District |
| Millmont Farm |
| Mill-Rae |
| Mill Tract Farm |
| Milmoral |
| Milton Armory |
| Milton Freight Station |
| Milton Historic District |
| Minersville Historic District |
| Mishler Theatre |
| Mitchell, James, House |
| Mitchell-Shook House |
| Mitchell, S. Weir, School |
| Mixsell, Jacob, House |
| Monastery, The |
| Monongahela Cemetery |
| Monroe County Courthouse |
| Monroe Tavern |
| Monterey Historic District |
| Monte Vista |
| Montgomery House |
| Montgomery Ward Building |
| Montgomery, William, House |
| Montrose Historic District |
| Moore, Capt. Thomas, House |
| Moore, Clarence B., House |
| Moore Hall |
| Moravian Pottery and Tile Works |
| Moravian Sun Inn |
| Moreland-Hoffstot House |
| Morgan, Edward, Log House |
| Morgantown Historic District |
| Morris, Anthony, House |
| Morris-Hair Tavern |
| Morrison, Andrew J., School |
| Morrow, John, Elementary School |
| Morse, Samuel F. B., School |
| Morton Homestead |
| Morton, Morton, House |
| Moselem Farms Mill |
| Most Precious Blood Roman Catholic Church, Rectory and Parochial School |
| Mother Bethel A.M.E. Church |
| Mountain Meadow Farm |
| Mountain Springs Hotel |
| Mount Airy Historic District |
| Mount Hope Estate |
| Mount Joy |
| Mount Pleasant |
| Mount Pleasant Armory |
| Mount Pleasant Historic District |
| Mount Pleasant Historic District |
| Mount Saint Mary Convent and Saint Benedict Academy Historic District |
| Mount St. Peter Roman Catholic Church |
| Mount Tabor AME Zion Church and Cemetery |
| Mount Union Historic District |
| Moxham Historic District |
| Moyer, John Nicholas and Elizabeth, House |
| Mt. Airy Station |
| Mt. Alvernia Historic District |
| Mt. Gretna Campmeeting Historic District |
| Mt. Pleasant Iron Works House |
| Muhlenberg, Henry Melchoir, House |
| Muhlenberg School |
| Muhr, Simon, Work Training School |
| Mulford Building |
| Mulford, Sylvanus, House |
| Mumma, Samuel N., Tobacco Warehouse |
| Munce, Thomas, House |
| Muncy Historic District |
| Municipal Building and Central Fire Station, 340 |
| Murray, Thomas, House |
| Nace (Neas), George, House |
| Narbrook Park Historic District |
| Nathan's Department Store |
| National Bank of Coatesville Building |
Data from United States Park Service and Wikidata
