All - Constructed - 1880–1889
| Latham Confederate Monument |
| Lauer Flats |
| Laurel Railroad Station |
| Lawler, W. T., House |
| Leadville National Fish Hatchery |
| Lea Laboratory |
| Leathers, H. G., House |
| Lebold, C. H., House |
| Lee House |
| LeFarriere House |
| Leffingwell-Batcheller House |
| Lemoine, Thomas A., House |
| Leonard, Velosco V., House |
| Lesinger Block |
| Letovsky-Rohret House |
| Le Vieux Presbytere |
| Lewis, Samuel, House |
| Lexington House |
| L. Hoster Brewing Company |
| Liberty Baptist Church |
| Liberty Hall |
| Liberty Lodge No. 123, F & A M |
| Liberty Park |
| Library Park Historic District |
| Lieuallen, Almon Asbury, House |
| Limon Railroad Depot |
| Lincoln Building |
| Lincoln Club |
| Lincoln County Courthouse |
| Lincoln School |
| Lindorff, Alfred, House |
| Linn County Courthouse |
| Lion Block |
| Lion Factory |
| Little Finnup House |
| Little Greenbrier School-Church |
| LITTLE JENNIE (Chesapeake Bay bugeye) |
| Little Walnut River Pratt Truss Bridge |
| Lockhardt, Charles H., House |
| Lord and Burnham Building |
| Lord, Richard T. C., and William V. Wilcox House |
| Lord's Castle |
| Los Candelarias Chapel-San Antonio Chapel |
| Loucks, Charles N., House |
| Lower Elgin Road Bridge at Wilbarger Creek |
| Lower Fox Creek School |
| Loys Station Covered Bridge |
| Lucy, the Margate Elephant |
| Luna, Tranquilino, House |
| Lunn-Musser Octagon Barn |
| Lyman Terrace |
| Lyon Street School |
| Machpelah |
| Macomber, Calvin T., House |
| Magnolia Mills |
| Magnolia Ranch |
| Magnolias, The |
| Maish House |
| Mallett Hall |
| Mallett Hall |
| Manchester Street Bridge |
| Manning-Kamna Farm |
| Mann-Zwonecek House |
| Manti City Hall |
| Manti Temple |
| Mari-Castle |
| Marion County Courthouse |
| Marsh School |
| Marstons Mills Hearse House and Cemetery |
| Martin, Aaron, House |
| Martin, Dr. G. S., House |
| Mask and Wig Club of the University of Pennsylvania |
| Masonic Temple Building |
| Mason, John W., House |
| Mast General Store |
| Mathewson-Gerecke House |
| Maxwell Park School |
| McAdory Building |
| McArthur-Martin Hexadecagon Barn |
| McClew, Alexander, Farm House |
| McConnell, W. J., House |
| McGill, Andrew R., House |
| McGlashan-Nickerson House |
| McJohnston Chapel and Cemetery |
| McKeeby, Dr. Gilbert, House |
| McLachlan, William, Farmhouse |
| McLemore House |
| McLeod Family Rural Complex |
| McMullin, Maj. James W., House |
| McNally, Andrew, House |
| McNeely House |
| McPherson Opera House |
| Meade, Capt. Matthew J., House |
| Meadowcroft, Charles, House |
| Melligan Store-Agriculture Hall |
| Mencken, H. L., House |
| Mercy Hospital and Elizabeth McDowell Bialy Memorial House |
| Merriam, Henry W., House |
| Merrill City Hall |
| Metcalf, James and Caroline M., House |
Data from United States Park Service and Wikidata
