Illinois - Significance region: Local
| Church of the Epiphany |
| Churchville School |
| City and Town Hall |
| City Building |
| Civilian Conservation Corps Camp Shiloh Encampment Site |
| Clarksburg Schoolhouse |
| Clay County Courthouse |
| Clay County Jail |
| Clayson, George, House |
| Clear Creek Meeting House |
| Cloud, Chalon Guard and Emma Blades, House |
| Coca-Cola Bottling Company Building |
| Coffeen, William and Helen, House |
| Colby-Petersen Farm |
| Coleman Hardware Company Building |
| Coles County Courthouse |
| Collins, Daniel Dove, House |
| Collinsville City Hall and Fire Station |
| Collinsville Masonic Temple Lodge #712 A.F. & A.M. |
| Collinsville Township High School |
| Colwell, E. B., and Company Department Store |
| Commercial House |
| Community House |
| Compton, Dr. Charles, House |
| Condit, Cortland, House |
| Condon Brothers and R.H. Shumway Building |
| Conger, J. Newton, House |
| Congress Theater |
| Connor House |
| Continental and Commercial National Bank |
| Cook County Criminal Court Building |
| Cook Memorial Library |
| Copley Hospital |
| Corbin Farm Site |
| Cornelia, The |
| Cornell Square |
| Country Tea Room |
| Count's House |
| Covell, Lucein Boneparte, House |
| Covent Hotel |
| Cox, George H., House |
| Craig and Estella Hazelwood House |
| Crane Company Building |
| Creamery Package Manufacturing Company Building |
| Crego, George M., Farm |
| Cumberland Presbyterian Church |
| Curtis, Elijah P., House |
| Curtiss-Wright Aeronautical University Building |
| Dale Building |
| Danville Branch, National Home for Disabled Volunteer Soldiers Historic District |
| Danville Public Library |
| Davis, David, III & IV, House |
| Davis Theater |
| Dawson Brothers Plant |
| Deere, John, House |
| Deerpath Hill Estates Historic District |
| Deerpath Inn |
| Delavan Commercial Historic District |
| Dell Rhea's Chicken Basket |
| Delta Kappa Epsilon Fraternity House |
| Delta Upsilon Fraternity House |
| Dement-Zinser House |
| Denhart Bank Building |
| Des Plaines Methodist Camp Ground |
| Dewey House |
| Dilg, Herbert A., House |
| Dilworth, Robert, House |
| Dixon Downtown Historic District |
| Dorhmann-Buckman House |
| Downey Building |
| Downtown Aledo Historic District |
| Downtown East St. Louis Historic District |
| Downtown Hinsdale Historic District |
| Downtown Joliet Historic District |
| Downtown Momence Historic District |
| Downtown Oswego Historic District |
| Downtown Peoria Historic District |
| Downtown Peotone Historic District |
| Downtown Plainfield Historic District |
| Downtown Rock Island Historic District |
| Downtown Urbana Historic District |
| Drake Hotel |
| Draser, George, Jr., House |
| Drucker, Robert and Suzanne, House |
| Dulaney, Robert L., House |
| Dunnan-Hampton House |
| Du Page County Courthouse |
| Dupont, John, House |
| Durant House |
| Durell, William Franklin and Rebecca, House |
| Durham-Perry Farmstead |
| Dutch Mill |
| Duvall-Ash Farmstead |
| Dycus, Floyd and Glenora, House |
| Eagle Hotel |
| East Dubuque School |
| East Grove Street District-Bloomington |
| East Park Towers |
| East Ravenswood Historic District |
| East Rockford Historic District |
Data from United States Park Service and Wikidata
