All - Constructed - 1920–1929
| Kingfisher Memorial Hall |
| Kingston Armory |
| Kingston-Port Ewen Suspension Bridge |
| Kirk Hotel, The |
| Kishenehn Ranger Station Historic District |
| Knickerbocker Hotel |
| Knights of Columbus Building |
| Knights of Columbus Building |
| Kochsmeier, Henry and Anna, House |
| Kootenai Creek Snowshoe Cabin |
| Krank Manufacturing Company |
| Kress, S.H., and Company Building |
| Kruse, Billy, Cabin |
| Kurth, Joseph H., Jr. House |
| Kyle Hotel |
| La Belle Tour |
| Laboratory of Anthropology |
| Labor Bank Building |
| La Casa del High Jinks |
| Ladywood Apartments |
| Lafayette Elementary School |
| Lafayette School |
| Lake Overholser Bridge |
| Lake Quinault Lodge |
| Lake Shore Apartments |
| Lake-Side Terrace Apartments |
| Lake View Grange No. 970 |
| La Luz Pottery Factory |
| Lamar Hotel |
| Lamont, Robert P., House |
| Lancaster Municipal Building |
| Lander County High School |
| Lane-Miles Standish Company Printing Plant |
| Langley High School |
| Lansdale Silk Hosiery Company-Interstate Hosiery Mills, Inc. |
| Lansing Artillery Michigan National Guard Armory |
| Lanzl, Haerman, House |
| Laramie County Milk Producers Cooperative Association |
| Larson Brothers Airport |
| LaSalle Apartments |
| La Salle Hotel |
| Latuda, Frank, House |
| Laughlin, Ben, Water Tank House-Garage |
| Lava Beds National Monument Archeological District |
| Lawrence, Dr. Elmo N., House |
| Lawyers Building |
| Leach Public Library |
| Leach, R.L., Grocery Store |
| Lecompte High School |
| Lee Creek Snowshoe Cabin |
| Leedy, Bert, Round Barn |
| Lee, Higginson & Company Bank Building |
| Lee, Jesse, Home for Children |
| Lee, Robert Edward, Scuplture |
| Leesburg High School |
| Leiffer House |
| Lemmon Rock Lookout House |
| Leonard, Clifford Milton, Farm |
| Lester River Bridge-Bridge No. 5772 |
| Leverett, William J., House |
| Levy, George, House |
| Lewis County Courthouse |
| Libbey, Edward Drummond, High School |
| Liberty Hotel |
| Library and Laboratory Building-Henderson Institute |
| Liggett Building |
| Light Hall |
| Lillybanks |
| Lincoln Arms Apartments |
| Lincoln County Courthouse |
| Lincoln Heights School |
| Lincoln Memorial |
| Lincoln Memorial Park Cemetery |
| Lincoln Road-Pine River Bridge |
| Lincoln School |
| Lincoln School |
| Lincoln School |
| Lincoln (Statue) |
| Lincoln Theater |
| Lincoln Theatre |
| Lincoln Theatre |
| Lindeman-Johnson House |
| Lindsay, Oscar, House |
| Linn, Howard and Lucy, House |
| Lithia Springs Hotel |
| Little Hell Canyon Bridge |
| Littleton Town Hall |
| Lochsa Historical Ranger Station |
| Locktown-Sergeantsville Road truss bridge over Plum Brook |
| Loeb, Alex, Building |
| Loew's and United Artists State Theatre |
| Loew's Kings Theatre |
| Loews Theatre |
| Logan Apartments |
| Lone Star School |
| Long Meadow Bridge |
| Longmire Buildings |
| Long, Robert Alexander, High School |
| Longue Vue Club and Golf Course |
| Longview Community Church-Saint Helen's Addition |
Data from United States Park Service and Wikidata
