Iowa - Criteria: A (event)
| Brown, James, House |
| Bruce Goldfish Fisheries |
| Bruce's Snowball Market #1 Addition |
| Bruguier, Theophile, Cabin |
| Bryn Mawr Apartments |
| Buchanan County Court House |
| Buchanan School |
| Buffalo High School |
| Buresh Farm |
| Burlington and Missouri River Railroad Passenger Station |
| Burlington, Cedar Rapids, and Minnesota Railroad: Walker Station |
| Burlington, Cedar Rapids and Northern Railroad Passenger Station |
| Burlington, Cedar Rapids, and Northern Railroad-Rock Rapids Station, Railroad Track and Bridge |
| Burlington, Cedar Rapids & Northern Freight House |
| Burlington, Cedar Rapids & Northern Passenger Depot-Dows |
| Burlington, Cedar Rapids & Northern Passenger Station-Vinton |
| Burlington Depot |
| Burlington Public Library |
| Burnett-Montgomery House |
| Burns United Methodist Church |
| Burr Oak House/Masters Hotel |
| Burr Oak Savings Bank |
| Buxton Historic Townsite |
| Byal Orchard Historic District |
| Calmar Passenger Depot |
| Campbell Baking Company |
| Camp Dodge Pool District |
| Camp Harlan-Camp McKean Historic District |
| Carnegie-Ellsworth Public Library |
| Carnegie Library |
| Carnegie Library Building |
| Carstens Farmstead |
| Case, Larnerd, House |
| Cass County Court House |
| Cassel, Carl and Ulrika Dalander, House |
| Cattermole Memorial Library |
| Caviness, Carl L., Post 102, American Legion |
| C B & Q Passenger Depot |
| Cedar County Sheriff's House and Jail |
| Cedar Falls Downtown Historic District |
| Cedar Falls Ice House |
| Cedar Falls Independent Order of Odd Fellows |
| Cedar Falls Post Office |
| Cedar Rapids 2nd Avenue SE. Automobile Row Historic District |
| Cedar Rapids Central Business District Commercial Historic District |
| Cedar Rapids Central Fire Station |
| Cedar Rapids Milk Condensing Company |
| Cedar Rapids Pump Company Factory and Warehouse |
| Cedar Valley Seminary |
| Central City Commercial Historic District |
| Central Fire Station |
| Chaffee-Hunter House |
| Chamberlain, D.S., Building |
| Chariton City Hall and Fire Station |
| Chariton Free Public Library |
| Charles City College Hall |
| Charles City Junior-Senior High School |
| Chautauqua Park |
| Chautauqua Park Historic District |
| Chautauqua Park Historic District |
| Chautauqua Pavilion |
| Cherokee Public Library |
| Chevra B'nai Yisroel Synagogue |
| Chicago and North Western Office Building/Passenger Depot-Lake City |
| Chicago and North Western Passenger Depot |
| Chicago, Burlington and Quincy Depot |
| Chicago, Burlington, and Quincy Freight House-Chariton |
| Chicago, Burlington and Quincy Railroad-Creston Station |
| Chicago, Burlington and Quincy Station |
| Chicago, Burlington Northern and Quincy Depot |
| Chicago, Great Western Railroad-Waterloo Freight Depot |
| Chicago, Milwaukee and Pacific Railroad-Albert City Station |
| Chicago, Milwaukee, and St. Paul Railroad-Grafton Station |
| Chicago, Milwaukee, St. Paul and Pacific Freight House |
| Chicago, Milwaukee, St. Paul and Pacific Railroad Company Depot |
| Chicago, Milwaukee, St. Paul & Pacific Combination Depot-Hornick |
| Chicago, Milwaukee, St. Paul & Pacific Depot-Delmar |
| Chicago, Rock Island and Pacific Passenger Depot-Pella |
| Chicago, Rock Island and Pacific Railroad Passenger Station |
| Chicago,Rock Island and Pacific Railroad: Stuart Passenger Station |
| Chicago, Rock Island and Pacific Railroad-Wilton Depot |
| Chicago, Rock Island & Pacific Railroad Depot |
| Chicago, Rock Island & Pacific Railroad Passenger Depot |
| Chief Black Hawk Statue |
| Chief Wapello's Memorial Park |
| Christian Petersen Courtyard Sculptures, and Dairy Industry Building |
| Church of St. John the Baptist |
| Church, Seymour, House |
| City Market |
| Civic Center Historic District |
| Civilian Conservation Corps-Prisoner of War Recreation Hall |
| Clarinda Carnegie Library |
| Clark-Blackwell House |
| Clark, Gerome, House |
| Clark Round Barn |
| Clayton County Courthouse |
| Clemens Automobile Company Building |
| Clinton Public Library |
| Coal Ridge Baptist Church and Cemetery |
| Cody Road Historic District |
Data from United States Park Service and Wikidata
