Illinois - Criteria: A (event)
| Building at 1301-1303 Judson Avenue |
| Building at 1305-1307 Judson Avenue |
| Building at 1316 Maple Avenue |
| Building at 1401-1407 Elmwood Avenue |
| Building at 1505-1509 Oak Avenue |
| Building at 1929-1931 Sherman Avenue |
| Building at 2517 Central Street |
| Building at 2519 Central Street |
| Building at 2523 Central Street |
| Building at 417-419 Lee Street |
| Building at 548-606 Michigan Avenue |
| Building at 5510 North Sheridan |
| Building at 813-815 Forest Avenue |
| Building at 923-925 Michigan Avenue |
| Building at 999 Michigan, 200 Lee |
| Buildings at 1104-1110 Seward |
| Buildings at 815-817 Brummel and 819-821 Brummel |
| Burgess-Osborne Memorial Auditorium |
| Butler School |
| Cairo Historic District |
| Calhoun, Mr. James Kent, House |
| Calumet Park |
| Calumet Plant, R. R. Donnelly & Sons Company |
| Cambre House and Farm |
| Campana Factory |
| Camp Butler National Cemetery |
| Campground Church and Cemetery Site |
| Camp Lincoln Commissary Building |
| Camp Logan National Guard Rifle Range Historic District |
| Camp Mather-Camp Logan |
| Camptown Town Hall |
| Carlinville Chapter House |
| Carmi Chapter House |
| Carrollton Courthouse Square Historic District |
| Carter, Frederick B., Jr., House |
| Carthage Courthouse Square Historic District |
| Castle Tower Apartments |
| Castlewood Terrace |
| Catlow Theatre |
| Cattle Bank |
| Cave-In-Rock |
| Cedar Crest Addition Historic District |
| Central Geneva Historic District |
| Central House |
| Centralia Commercial Historic District |
| Central Manufacturing District-Original East Historic District |
| Central Manufacturing District-Pershing Road Development Historic District |
| Central Park Theater |
| Chain of Rocks Bridge |
| Champaign Downtown Commercial District |
| Chanute Field Historic District |
| Chautauqua Auditorium |
| Chemical Laboratory |
| Chicago and Eastern Illinois Railroad Depot |
| Chicago and Northwestern Depot |
| Chicago and Northwestern Depot |
| Chicago and North Western Railroad Depot |
| Chicago and North Western Railway Power House |
| Chicago Beach Hotel |
| Chicago Bee Building |
| Chicago Board of Trade Building |
| Chicago, Burlington, and Quincy Railroad Depot |
| Chicago, Burlington, and Quincy Railroad Depot |
| Chicago, Burlington & Quincy Railroad Depot |
| Chicago, Burlington & Quincy Railroad Depot |
| Chicago, Burlington & Quincy Railroad Station |
| Chicago Club |
| Chicago Federal Center |
| Chicago Great Western Railroad Depot |
| Chicago Harbor Lighthouse |
| Chicago, Milwaukee and St. Paul Railway Passenger Depot |
| Chicago & North Western Railway Stone Arch Bridge |
| Chicago Portage National Historic Site |
| Chicago, Rock Island and Pacific Railroad Depot |
| Chicago Sanitary and Ship Canal Historic District |
| Chicago Savings Bank Building |
| Chicago Telephone Company Kedzie Exchange |
| Chick House |
| Chipman, Edward, Public Library |
| Christ Church of Lower Kickapoo |
| Christian Hill Historic District |
| Churchville School |
| City and Town Hall |
| City Building |
| Clarksburg Schoolhouse |
| Clay County Jail |
| Clayville Tavern |
| Clear Creek Meeting House |
| Cloud State Bank |
| Coca Cola Company Building |
| Coleman Hardware Company Building |
| Coles County Courthouse |
| Collinsville City Hall and Fire Station |
| Collinsville Masonic Temple Lodge #712 A.F. & A.M. |
| Colonnade Court |
| Columbus Park |
| Colwell, E. B., and Company Department Store |
| Commercial House |
| Community House |
| Condit, Cortland, House |
Data from United States Park Service and Wikidata
