Pennsylvania - Significance region: Local
| Meier, Isaac, Homestead |
| Meinig Glove Factory-Meinig, E. Richard, Co. |
| Melchinger, Englehart, House |
| Melester Barn |
| Mellon Park |
| Melrose |
| Memorial Church of Our Father |
| Memorial Fountain and Statue |
| Memorial Park Site |
| Memorial Presbyterian Church |
| Mentzer Building |
| Mercersburg Academy |
| Mercersburg Historic District |
| Merchants Cigar Box Company |
| Meredith, Daniel, House |
| Meredith, Simon, House |
| Meredith, Stephen, House |
| Meredith, William M., School |
| Merit Underwear Company |
| Merkel Mill |
| Merkel Mill Complex |
| Merrick Art Gallery |
| Merrill Lock No. 6 |
| Methodist Episcopal Church of Burlington |
| Metropolitan Edison Building |
| Metz Ice Plant |
| Mexican War Streets Historic District |
| Meyerhoff, Son and Company Building |
| Michael, John, Farm |
| Michener, Nathan, House |
| Middishade Clothing Factory |
| Middlekauff, Jacob and Juliana, House |
| Middle Pickering Rural Historic District |
| Midland Cemetery |
| Midtown Harrisburg Historic District |
| Mifflin County Courthouse |
| Mifflin Elementary School |
| Mifflin School |
| Mifflin, Thomas, School |
| Milanville Historic District |
| Miles-Humes House |
| 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 |
| Miller, Longdon L., Covered Bridge |
| Millersburg Ferry |
| 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 |
| Millmont Red Bridge |
| Mill Rift Hall |
| Milmoral |
| Milton Freight Station |
| Milton Historic District |
| Minersville Coke Ovens |
| Minersville Historic District |
| Mingo Creek Presbyterian Church and Churchyard |
| Mishler Theatre |
| Mitchell, James, House |
| Mitchell-Shook House |
| Mitchell, S. Weir, School |
| Mixsell, Jacob, House |
| Modern Tool Company |
| Moland House |
| Monongahela Cemetery |
| Monongahela Incline |
| Monroe County Courthouse |
| Monroe Furnace |
| Monroe Tavern |
| Monte Vista |
| Montgomery House |
| Montgomery Ward Building |
| Montgomery, William, House |
| Montrose Historic District |
| Mooncrest Historic District |
| Moore Hall |
| Mooresburg School |
| 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, Morton, House |
| Mortonville Hotel |
| Moselem Farms Mill |
| Mosier, Dr. J. R., Office |
| Most Precious Blood Roman Catholic Church, Rectory and Parochial School |
| Mothers’ Memorial, Hoffman Memorial, and Veterans’ Memorial |
Data from United States Park Service and Wikidata
