All - Architectural style - Italianate architecture
| LeClaire, Antoine, House |
| Leftwich House |
| Lemoine, Thomas A., House |
| Lenert, Dr. Robert, House |
| Leonard, Velosco V., House |
| Lesinger Block |
| Letovsky-Rohret House |
| Levering Hall |
| Lewis, Gov. James T., House |
| Libby-Hill Block |
| Lichtstern House |
| Light, Jacob, House |
| Lilly, Augustus, House |
| Lion Block |
| Little Brick House |
| Little Campus |
| Little Finnup House |
| Little Sable Point Light Station |
| Live Oak County Jail |
| Locke, Asa, House |
| Locust Grove |
| Long, J. G. and Regina, House |
| Longmont College |
| Longwood |
| Lowenstein House |
| Lower Fox Creek School |
| Lucas County Courthouse Square Historic District |
| Ludington House |
| Luethstrom-Hurin House |
| Luick, William Henry, Farmhouse |
| Lyons, Horace G., House |
| Maas Commercial Building |
| Mabey, Albert and Celestine, House |
| Madsen, David and Evinda, House |
| Magnolia Manor |
| Magnolias, The |
| Main and Third Street Cluster |
| Main Street Historic District |
| Maish House |
| Manatt, William, House |
| Mann, John, House |
| Mann, John Wesley, House |
| Mann-Zwonecek House |
| Mansion House |
| Manti City Hall |
| Maplewood |
| Marine Hospital |
| Market Square |
| Marks, Morris, House |
| Marshalldale |
| Marshall's Store |
| Martens, Julius J., Company Building |
| Martin, Dr. G. S., House |
| Martin, S. F., House |
| Masonic Building |
| Masonic Temple |
| Masonic Temple Building |
| Mason, John, House |
| Mason, John W., House |
| McCallum, William, House |
| McCandless Building |
| McClew, Alexander, Farm House |
| McClurg Building |
| McCord, William Harrison, House |
| McCoy Farmhouse |
| McCrea, Matthew, House |
| McFarlane, Andrew and Jennie, House |
| McGlashan-Nickerson House |
| McMinn Building |
| Meade, Capt. Matthew J., House |
| Mebane-Nuckolls House |
| Mechanics Engine House No. 4 |
| Mecklenburg's Garden |
| Melcher, Dennis Melcher, Pottery and House |
| Melligan Store-Agriculture Hall |
| Melvin, Isaac, House |
| Meridian Museum of Art |
| Merrehope |
| Merriam, Galen, House |
| Merritt Beach & Son Building |
| Merritt, Captain, House |
| Merritt, Samuel T., House |
| Metcalfe County Kentucky Courthouse |
| Michaels Farm |
| Millar-Wheeler House |
| Millen-Schmidt House |
| Miller, J. Z., House |
| Mills, Simeon, House |
| Miner House |
| Minster Elementary School |
| Mississippi Mills Packing and Shipping Rooms |
| Mohrman-Jack-Evans House |
| Monastery of Our Lady of Charity |
| Monroe County Courthouse |
| Montauk |
| Monteigne |
| Moore, John and Helen, House |
| Moormann, Bernard H., House |
| Morgan County Courthouse |
| Morgan-Skinner-Boyd Homestead |
Data from United States Park Service and Wikidata
