Iowa - Significance region: National
| Alleman, Richard L. and Verda M., Farm Historic District |
| Amana Villages |
| Bastian Site |
| Belknap, Gen. William Worth, House |
| Blood Run Site |
| Brewster Site |
| Catalpa |
| Cherokee Sewer Site |
| City National Bank Building |
| Coffin, Lorenzo S., Burial Plot |
| Cummins, Albert Baird, House |
| Darling, Jay Norwood and Genevieve Pendleton, House |
| Davis Oriole Earthlodge Site |
| Des Moines Art Center |
| Dodge, Grenville M., House |
| Douglas, George B., House |
| Dow House |
| Dubuque City Hall |
| Dubuque County Jail |
| Dubuque Trading Post-Village of Kettle Chief Archeological District |
| Effigy Mounds National Monument |
| Fort Atkinson Historic District |
| Fort Des Moines Provisional Army Officer Training School |
| Garst, Roswell and Elizabeth, Farmstead Historic District |
| GEO. M. VERITY |
| Glenwood Archeological District |
| Grand Opera House |
| Great Northern Railway Steam Locomotive No. 1355 and Tender 1451 |
| Harlan-Lincoln House |
| Henn Mansion |
| Hepburn, Col. William Peters, House |
| Herbert Hoover National Historic Site |
| Hitchcock, Rev. George B., House |
| Indian Village Site |
| Keokuk Lock and Dam |
| Keokuk National Cemetery |
| Kimball Village |
| Kirkwood House |
| Knapp-Wilson House |
| Langworthy House |
| Lewelling, Henderson, House |
| Lincoln School |
| Lock and Dam No. 12 Historic District |
| Lock and Dam No. 14 Historic District |
| Lock and Dam No. 16 Historic District |
| Lock and Dam No. 19 Historic District |
| LONESTAR |
| Marsh Rainbow Arch Bridge |
| McKee Button Company |
| Melan Bridge |
| Merchants' National Bank |
| Miller, Justice Samuel Freeman, House |
| Miller, Norris, House |
| Old Capitol |
| Old Fort Madison Site |
| Oleson Park Music Pavilion |
| Park Inn Hotel |
| Phipps Site |
| Plum Grove |
| Polled Hereford Breed Origin Site |
| Poplar Rural District |
| Pottawattamie County Jail |
| Reeve Electric Association Plant |
| Rock Crest-Rock Glen Historic District |
| Rogers, George W. Company Shot Tower |
| Salisbury House |
| SERGEANT FLOYD |
| Sergeant Floyd Monument |
| Sheaffer, Walter A., House |
| Spirit Lake Massacre Log Cabin |
| Stockman, Dr. G. C., House |
| Surf Ballroom |
| Terrace Hill |
| Todd House |
| Toolesboro Mound Group |
| Van Allen Store |
| Village of St. Donatus Historic District |
| Walter, Lowell E., House |
| Weaver, James B., House |
| West Oak Forest Earthlodge Site |
| WILLIAM M. BLACK (dredge) |
| Williges Building |
| Wilson, US Senator James F., House |
| Wolf, Mier, House |
| Woodbury County Courthouse |
| Yelland, Curtis, House |
Data from United States Park Service and Wikidata
