Iowa - Role: Building
| Henry County Savings Bank |
| Henryson, Henry T. and Emilie (Wiese), House |
| Henshie-Briggs Row House |
| Henyon-Kasper-Duffy Barn |
| Hepburn, Col. William Peters, House |
| Herman, John H., House |
| Herndon Hall |
| Herring Hotel |
| Herring Motor Car Company Building |
| Hibernia Hall |
| Hickman-Nietert-Odd Fellows Building |
| Highlandville School |
| Hiller Building |
| Hillside |
| Hippee Building |
| Hitchcock, Rev. George B., House |
| Hoag, J. J., House |
| Hobson Block |
| Hoersch, John, House |
| Hoffman Building |
| Hoffman, Phil, House |
| Hoffman, Samuel, Jr., House |
| Hofmann Building |
| Hohberger Building |
| Holbrook, William, House |
| Holdoegel, Perry C. and Mattie Forrest, House |
| Holland, Ora, House |
| Hollenfelz House |
| Holmes, John S. and Elizabeth Beem, Barn |
| Holtkamp Round Barn |
| Holy Trinity Greek Orthodox Church |
| Home Federal Savings and Loan Association of Des Moines Building |
| Home of Marshall's Horseradish |
| Home Oil Service Station |
| Homestead Building |
| Honey Creek Friends' Meetinghouse |
| Hoosier Row School |
| Hope Fire Company Engine House |
| Hornback, Emily, House |
| Horn House |
| Horton-Suiter House |
| Hose Station No. 1 |
| Hose Station No. 6 |
| Hose Station No. 7 |
| Hotel Burlington |
| Hotel Charitone |
| Hotel Chieftain |
| Hotel Fort Des Moines |
| Hotel Greenfield |
| Hotel Hurst |
| Hotel Hurst Garage |
| Hotel Iowa |
| Hotel Kirkwood |
| Hotel Lester-Lester Cafe |
| Hotel Manning |
| Hotel Mealey |
| Hotel Mississippi-RKO Orpheum Theater |
| Hotel Ottumwa |
| Hotel President |
| Hotel Randolph |
| Hotel Rea |
| Hotel Roosevelt |
| Hotel Russell-Lamson |
| Hotel Tipton |
| Hotel Whitney |
| House at 111 E. Maple Street |
| House at 1646 W. Second Street |
| House at 2123 W. Second Street |
| House at 2212 W. River Drive |
| House at 318-332 Marquette Street |
| House at 505 Court Street |
| House at 919 Oneida Street |
| Howard County Courthouse |
| Howes Building |
| Hubbell Building |
| Hubbell Warehouse |
| Hughes, David and M. Maria, House |
| Hughes-Irons Motor Company |
| Hughes, Martin, House |
| Hulme, Samuel and Sarah, House |
| Hult, Charles E., House, Summer Kitchen and Wood Shed |
| Humboldt County Court House |
| Humboldt Free Public Library |
| Hunter School |
| Hurst, A. A., House |
| Ida County Courthouse |
| Illinois Central Combination Depot-Ackley |
| Illinois Central Passenger Depot-Storm Lake |
| Immanuel Danish Evangelical Lutheran Church |
| Indianola Carnegie Library |
| Indianola High School |
| Ingemann Danish Evangelical Lutheran Church and Cemetery |
| Insane Asylum at the County Poor Farm |
| Interior Telephone Company Building |
| International Harvester Truck Sales and Service Station |
| Interstate Power Company Building |
| IOOF Building |
| I.O.O.F. Hall |
| I.O.O.F. Hall |
| I.O.O.F. (International Order of Odd Fellows) Valley Junction Lodge Hall No. 604 |
Data from United States Park Service and Wikidata
