Pennsylvania - Area of significance: Commerce
| Hess, A. B., Cigar Factory, and Warehouses |
| Highland Building |
| Hite House |
| Holicong Village Historic District |
| Hollidaysburg Historic District |
| Hopwood-Miller Tavern |
| Hotel Fauchere and Annex |
| Hotel Lykens |
| Hotel Pennsylvania |
| Howell and Brothers Paper Hangings Manufactory |
| Hulmeville Historic District |
| Hunter's Mill Complex |
| Huntingdon Borough Historic District |
| Hunt, Roger, Mill |
| Insurance Company of North America Building |
| Integrity Title Insurance, Trust and Safe Deposit Company |
| International Harvester Company of America: Pittsburgh Branch House |
| Johnsonburg Commercial Historic District |
| Johnson-Hatfield Tavern |
| Jones and Laughlin Steel Company Building |
| Kahn, Harry C. and Son, Warehouse |
| Karolcik Building |
| Kaufmann's Department Store Warehouse |
| Kelly, Amos, House |
| Kemp's Hotel |
| Kennett Square Historic District |
| Keswick Theatre |
| Kimberton Village Historic District |
| Kirks Mills Historic District |
| Knapp, Joseph, Hotel and Store |
| Knauer, John, House and Mill |
| Koehler, Jackson, Eagle Brewery |
| Krauskap, Henry, House, and Store |
| Kurtz, T. M., House |
| Kuster Mill |
| Lackawanna Avenue Commercial Historic District |
| Lady Washington Inn |
| Lancaster City Historic District |
| Lancaster Historic District |
| Landis Homestead |
| Langhorne Historic District |
| Larkin-Belber Building |
| Lawrenceville Historic District |
| Lehigh Canal |
| Lehigh Canal; Allentown to Hopeville Section |
| Lehigh Canal: Eastern Section Glendon and Abbott Street Industrial Sites |
| Leidy, Dr. Joseph, House |
| Lerch Tavern |
| Lewisburg Historic District |
| Ligonier Historic District |
| Linden Grove Pavilion |
| Linden House |
| Lionville Historic District |
| Lititz Moravian Historic District |
| Lits Department Store |
| Little, Moses, Tavern |
| Locomotive No. 6755 |
| Log House, Hiester House, and Market Annex |
| Lukens Historic District |
| Lumberville Historic District |
| Lunn's Tavern |
| Lutz, John F., Furniture Co. & Funerary |
| Manayunk Main Street Historic District |
| Manheim Borough Historic District |
| Mansfield |
| Markle Banking & Trust Company Building |
| Marklesburg Historic District |
| Marshallton Historic District |
| Marshallton Inn |
| Martin Tower |
| McKeesport National Bank |
| Meadville Downtown Historic District |
| Mechanicsburg Commercial Historic District |
| Mechanicsville Village Historic District |
| Meinig Glove Factory-Meinig, E. Richard, Co. |
| Mentzer Building |
| Mercersburg Historic District |
| Metropolitan Edison Building |
| Mifflinburg Historic District |
| Mikado Freight Locomotive No. 520 |
| Milford Historic District |
| Miller's Store |
| Millmont Farm |
| Milton Historic District |
| Mitchell, James, House |
| Modern Tool Company |
| Monroe Tavern |
| Montgomery Ward Building |
| Moravian Sun Inn |
| Morgantown Historic District |
| Morris-Hair Tavern |
| Mount Pleasant Historic District |
| Mount Union Historic District |
| Muddy Creek Forks Historic District |
| Muncy Historic District |
| Nathan's Department Store |
| National Transit Building |
| Nazareth Historic District |
| New Colonial Hotel |
| New Geneva Historic District |
Data from United States Park Service and Wikidata
