All - Constructed - 1850–1859
| House at 23 Avon Street |
| House at 25 Clyde Street |
| House at 25 High School Avenue |
| House at 25 Stanton Road |
| House at 309 Waltham Street |
| House at 31 Woodbine Street |
| House at 37 Center Street |
| House at 3 Davis Avenue |
| House at 42 Hopkins Street |
| House at 461 Spruce Lake Road |
| House at 5 Lincoln Road |
| House at 60 William Street |
| House at 6112 Carpenter Road |
| House at 729 Dedham Street |
| House at 7 Salem Street |
| House at 8 Park Street |
| Howard, John W., House and Outbuildings |
| Howe School |
| Huey, Thomas, Farm |
| Huger, Cleland Kinloch and Burnet R. Maybank, House |
| Hull House |
| Humpback Bridge |
| Huntingdon College Campus Historic District |
| Hunting Island State Park Lighthouse |
| Hunt-Moore House |
| Hunt,Samuel, House |
| Hurd House-Anderson Hotel |
| Huston House |
| Hutsell, Sam, House |
| Hver-Knowles Planing Mill Chimney |
| Hyer's Hotel |
| Ida Lewis Rock Lighthouse |
| Imbrie Farm |
| Independence Presbyterian Church |
| Indian Island Light Station |
| Ingalsbe, Adolphus and Sarah, House |
| Inglewood |
| Institute Hall |
| International Boundary Marker No. 1, U.S. and Mexico |
| Inzer House |
| Iowa County Courthouse |
| Irvin Hall, Highland Community Junior College |
| Island Home |
| Jackson, Mitchell, Farmhouse |
| Jacksonville, Pensacola and Mobile Railroad Company Freight Depot |
| Jacobs, Eugene, House |
| Jagger-Churchill House |
| Jarman Farm |
| Jarves, John and Mary Waterman, House |
| Jarvis, Anna, House |
| Jarvis House |
| Jefferson County Jail |
| Jewett-Eastman House |
| Johnson, Alphonso, House |
| Johnson-Hubbard House |
| Johnson, J. Neely, House |
| Johnston, James, House |
| Jones House |
| Keegan House |
| Kellogg, Miles and Elizabeth Smith, House |
| Kemp Barn |
| Kemp Place |
| Kendall Inn |
| Kenmore Farm |
| Kenney, David, House |
| Kidder, Asahel, House |
| Kimball, W.W., House |
| King Ranch |
| Kingston Methodist Church |
| Kliese Housebarn |
| Knight Cabin |
| Knott, Adams R., Frederick L. and Martha (Taylor), House |
| Knox Farm Historic District |
| Lafourche Parish Courthouse |
| Lake O'Woods |
| Lake Township School |
| Landmark Inn Complex |
| Landsberger-Gerhardt House |
| Lansdowne |
| Lappin-Hayes Block |
| Lardner, Ring, House |
| Last Chance Store |
| Lebanon Presbyterian Church |
| LeClaire, Antoine, House |
| Lefort House |
| Leitch, William T., House |
| Lewis, Gov. James T., House |
| Lewis-Smith House |
| Liberty Baptist Church |
| Liberty Hall |
| Liberty Presbyterian Church |
| Liddle, Alexander, Farmhouse |
| Linden Methodist Church |
| Lind, Jenny, Chapel |
| List, Henry K., House |
| Littell, David, House |
| Little, John Phillips, House |
| Little-Stabler House |
| Little White Schoolhouse |
| Lloyd Harbor Lighthouse |
Data from United States Park Service and Wikidata
