C
- Civilian Conservation Corps (65)
- clapboard siding (147)
- Classical Revival architectural elements (24)
- classrooms (26)
- cleaning establishments (1)
- cleaning (3)
- clerestories (4)
- cliff dwellings (5)
- clinics (52)
- clipper ships (1)
- clock & watch industry (1)
- clock towers (7)
- clothing industry (2)
- clothing stores (9)
- clubhouses (76)
- clubs (associations) (24)
- coal bins (2)
- coal chutes (1)
- coal gasification (1)
- coal mines (8)
- coal mining (14)
- coal tipples (5)
- coaling stations (3)
- coal (31)
- cobbler's shops (4)
- cobblestone streets (2)
- coffee industry (11)
- coffee roasters (1)
- coffee shops (1)
- coffeehouses (1)
- coffers (ceilings) (2)
- coke industry (7)
- coke ovens (6)
- coke plants (3)
- cold storage rooms (6)
- Cold War (80)
- collective settlements (14)
- colleges & universities (138)
- Colonial architectural elements (10)
- Colonial Revival architectural elements (9)
- colonial revival (15)
- colonnades (2)
- columns (29)
- commemoration (2)
- commerce (444)
- commercial art galleries (3)
- commercial facilities (696)
- commodity exchanges (1)
- common bond (4)
- communal living (18)
- communication facilities (9)
- communication (9)
- community centers (33)
- community service (2)
- company stores (10)
- company towns (26)
- complexes (31)
- compressors (4)
- concentration camps (1)
- concert halls (5)
- concourses (2)
- concrete arch bridges (236)
- concrete arches (8)
- concrete balustrades (1)
- concrete block buildings (63)
- concrete block construction (9)
- concrete bridges (28)
- concrete buildings (61)
- concrete flumes (1)
- concrete foundations (10)
- concrete girder bridges (41)
- concrete piers (1)
- concrete slabs (3)
- concrete truss bridges (1)
- concrete walls (1)
- concrete (512)
- condominiums (2)
- confectioneries (4)
- conference rooms (3)
- Congregational churches (70)
- conservation & restoration (65)
- conservatories (4)
- consoles (architectural elements) (4)
- consulates (5)
- control rooms (6)
- control towers (4)
- convenience stores (1)
- convents (30)
- cookery (19)
- cooling towers (4)
- cooper shop (2)
- cooperatives (3)
- coopers (1)
- coping (2)
- copper industry (6)
- copper mining (15)
- corbels (2)
- Corinthian order (14)
- corn cribs (35)
- cornices (14)