Pennsylvania - Significance region: Local
| Isett, Jacob, House and Store |
| Israel Building |
| Ivyland Historic District |
| Jackson Mansion and Carriage House |
| Jacksons Mill Covered Bridge |
| Jacobs, Benjamin, House |
| Jacobsburg Historic District |
| James, Morgan, Homestead |
| Jayne, Horace, House |
| Jefferson Avenue School |
| Jefferson Elementary School |
| Jefferson. John P., House |
| Jefferson Land Association Historic District |
| Jefferson Theater |
| Jefferson, Thomas, School |
| Jenkins Homestead |
| Jenkins' Town Lyceum Building |
| Jenkintown Wyncote Train Station |
| Jenks, John Story, School |
| Jennings-Gallagher House |
| Jersey Shore Historic District |
| Joanna Furnace Complex |
| John's Burnt Mill Bridge |
| Johnsonburg Commercial Historic District |
| Johnson Covered Bridge No. 28 |
| Johnson-Hatfield Tavern |
| Johnson, Nicholas, Mill |
| Jones and Laughlin Steel Company Building |
| Jones, B. F., Memorial Library |
| Jones, James, House |
| Jones, John Paul, Junior High School |
| Josiah Hess Covered Bridge No. 122 |
| Jud Christie Covered Bridge No. 95 |
| Juniata Iron Works |
| Juniata Terrace Historic District |
| Juvenile and Domestic Branches of the Municipal Court |
| Kagerise Store and House |
| Kahn, Harry C. and Son, Warehouse |
| Kane, Thomas L., Memorial Chapel |
| Karolcik Building |
| Kastner, Jacob, Loghouse |
| Kauffman Mill |
| Kaufmann's Department Store Warehouse |
| Keefe-Mumbower Mill |
| Keefer Covered Bridge No. 7 |
| Keefer Station Covered Bridge |
| Keith, D.S., Junior High School |
| Keller, Jacob, Farm |
| Kelly, Amos, House |
| Kemmerer House |
| Kemp's Hotel |
| Kenderdine Mill Complex |
| Kennedy, Francis W., House |
| Kennedy Mansion |
| Kennedy, Robert, Memorial Presbyterian Church |
| Kennett Square Historic District |
| Kensington Branch of the Philadelphia YWCA |
| Kensington High School for Girls |
| Kent, Thomas, Jr., Farm |
| Kerr, Thomas R., Dr., House and Office |
| Keswick Theatre |
| Key, Francis Scott, School |
| Keystone Building |
| Keystone Hook and Ladder Company |
| Keystone Hotel |
| Keystone Mill |
| Kidd's Mills Covered Bridge Historic District |
| Kimberton Village Historic District |
| Kinbawn |
| Kinder's Mill |
| King of Prussia Inn |
| King's Bridge |
| Kinsey, John L., School |
| Kintersburg Covered Bridge |
| Kirkbride, Eliza Butler, School |
| Kirk Johnson Building |
| Kirkland Station |
| Kirks Mills Historic District |
| Kirk, William, House |
| Kise Mill Bridge Historic District |
| Kissling Farm |
| Kistler Residence |
| Kitchen, William, House |
| Kitson Woolen Mill |
| Kittanning Passenger Station and Freight Depot |
| Knabb-Bieber Mill |
| Knapp Farm |
| Knapp, Joseph, Hotel and Store |
| Knapp's Covered Bridge |
| Knauer, John, House and Mill |
| Knauss, Heinrich, House |
| Knickerbocker Historic District |
| Knipe-Johnson Farm |
| Knipe-Moore-Rupp Farm |
| Knisley, Dr., Covered Bridge |
| Knoebel, Lawrence L., Covered Bridge |
| Knorr-Bare Farm |
| Knoxville Junior High School |
| Knurr Log House |
| Koehler, Jackson, Eagle Brewery |
Data from United States Park Service and Wikidata
