- 1 City Museum and Theatre
- 3 City Parks Association
- 4 City planning
- 2 City Railroad Stable
- 1 City Railroad Station
- 5 City Tavern
- 1 City Tobacco Warehouse
- 1 City walls
- 5 Cityscape prints
- 68 Cityscapes
- 14 Civic Center Boulevard
- 1 Civil engineering
- 2 Civil engineers
- 22 Civil law
- 9 Civil rights leaders
- 1 Civil service reform
- 344 Civil War, 1861-1865
- 2 Civil wars
- 2 Claghorn, James Lawrence, 1814-1889
- 2 Clapboard siding
- 1 Clapp & Greenwood's Factory
- 1 Clare, of Assisi, Saint, 1194-1253
- 4 Clarinets
- 1 Clark & Son's Painting
- 1 Clark and Beatty (Hosiery)
- 2 Clark Park
- 2 Clark Thread Co.
- 7 Clark, C.H. Lumber Yard
- 1 Clarke, Campbell
- 1 Clarke, Charles Cowden, 1787-1877
- 2 Clarke, John Gold Leaf Factory
- 1 Clarke, Mary Cowden, 1809-1898
- 1 Clarrisa Harlowe
- 2 Clasps (fasteners)
- 1 Classical Institute
- 4 Classical Institute
- 7 Classical Revival (European revival style)
- 3 Classrooms
- 1 Clavichords
- 3 Claxton, Remsen & Haffelfinger