Indiana - Area of significance: Architecture
| Carpenter, Willard, House |
| Carr High School |
| Carroll County Courthouse |
| Carroll County Infirmary |
| Carr's Hall |
| Carter-Randall-Parker House |
| Cascades Park |
| Cathcart |
| Cathedral of St. James and Parish Hall |
| Cathedral of the Immaculate Conception |
| Catherine Street Historic District |
| CCC Recreation Building-Nature Museum |
| Cedar Bough Place Historic District |
| Cedar Lodge |
| Cedar Point Farm |
| Centennial Neighborhood District |
| Center Ridge Cemetery |
| Center Township Grade and High School |
| Centerville Historic District |
| Central Avenue School |
| Central Batesville Historic District |
| Central Court Historic District |
| Central High School & Boys Vocational School |
| Central House |
| Centralia Court Historic District |
| Central Library |
| Central Library (Indianapolis-Marion County Public Library) |
| Chapin, Horatio, House |
| Chapin Park Historic District |
| Chatham-Arch Historic District |
| Chauncey-Stadium Avenues Historic District |
| Chenoweth-Coulter Farm |
| Chesterton Commercial Historic District |
| Chesterton Residential Historic District |
| Christ Church Cathedral |
| Christian, John E. and Catherine E., House (Samara) |
| Christian Park School No. 82 |
| Christian Ridge Historic District |
| Chute, Haller T., Building |
| Circle Theater |
| Citizens Bank |
| Citizens National Bank |
| Citizens' Trust Company Building |
| City Hall |
| City Market |
| Clark-McKinley Historic District |
| Clark, Orin, House |
| Clark, Wellington A., House |
| Clay County Courthouse |
| Clay County Hospital |
| Clifford, Patrick and Catherine, House |
| Cline, Cyrus and Jennie, House |
| Clinton County Courthouse |
| Clore Plow Works-J.W. Whitlock and Company |
| Cloverdale Historic District |
| Coambs, Norris and Harriet, Lustron House |
| Coburn, Henry P., Public School No. 66 |
| Coca-Cola Bottling Company Plant |
| Coca-Cola Bottling Plant |
| Cochran-Helton-Lindley House |
| Cockrum, William M., House |
| Cole-Evans House |
| Cole, James Omar, House |
| Cole, Joseph J., Jr., House |
| Colfax Carnegie Library |
| Collett Park Neighborhood Historic District |
| Collins School |
| Colman-Doctor Farm |
| Colonial |
| Colonial Gardens Commercial Historic District |
| Colored Knights of Pythias Castle Hall |
| Colter, Ben, Polygonal Barn |
| Columbia City Historic District |
| Columbia Club |
| Columbus City Hall |
| Columbus Historic District |
| Combination Shelter |
| Combs Addition Historic District |
| Commercial Building |
| Condit House |
| Condon, Charles H. and Emma, House |
| Conklin-Montgomery House |
| Conn, Charles Gerard, Mansion |
| Conner's Bookstore |
| Conner Street Historic District |
| Connersville Downtown Historic District |
| Conner, William, House |
| Convent Immaculate Conception Historic District |
| Converse Commercial Historic District |
| Converse Depot |
| Converse-Jackson Township Public Library |
| Conwell, Elias, House |
| Cooper-Alley House |
| Coppes, Frank and Katharine, House |
| Corbin, Roy and Iris, Lustron House |
| Cornell, William, Homestead |
| Corydon Historic District |
| Cottage Home Historic District |
| Coulter Flats |
| Courthouse Historic District |
Data from United States Park Service and Wikidata
