New York - Significance region: Local
| Conkey House |
| Conklin, David, House |
| Conklin Farm |
| Conkling-Boardman-Eldridge Farm |
| Conklin Mountain House |
| Conklin, Nathaniel, House |
| Conklin Town Hall |
| Connecticut Street Armory |
| Connors, William, Paint Manufacturing Company Building |
| Consolidated Car Heating Company Complex |
| Constableville Village Historic District |
| Continental Baking Company Factory |
| Coolidge Stores Building |
| Coons, Charles H., Farm |
| Coons House |
| Cooper Avenue Row Historic District |
| Copake Falls Methodist Episcopal Church |
| Copake Grange Hall |
| Copake Memorial Clock |
| Copake Railroad Depot |
| Copake United Methodist Church and Copake Cemetery |
| Copcutt,John,Mansion |
| Copeland Carriage Shop |
| Copeland Covered Bridge |
| Coppola House |
| Corbin Building |
| Corby Farm Complex |
| Cordts Mansion |
| Corey Cottage |
| Corlies-Ritter-Hart House |
| Corliss Park Historic District |
| Cornelia-Putnam Historic District |
| Cornell Farmhouse |
| Cornell Heights Historic District |
| Cornell-Manchester Farmstead |
| Cornell-Van Nostrand House |
| Cornfield, The |
| Corning Armory |
| Cornwall Brothers' Store |
| Cornwall Friends Meeting House |
| Cornwallville Cemetery |
| Corpus Christi R.C. Church Complex |
| Cortland County Courthouse |
| Cortland County Poor Farm |
| Cortland Fire Headquarters |
| Cortland Free Library |
| Corwith, William, House |
| Cosman Family Cemetery |
| Cottage Farm |
| Cottage in the Pines |
| Cottage Lawn |
| Cottage Row Historic District |
| Cottages at Central Point |
| Coulter Cottage |
| County and City Hall |
| County Farm |
| Courier Building, The |
| Court Exchange Building-National Casket Company |
| Court Street Bridge |
| Court Street Historic District |
| Court Street Historic District |
| Coverdale Cobblestone House |
| Covert Historic District |
| Covert, William, Cobblestone Farmhouse |
| Covewood Lodge |
| Cowles, W.T., House |
| Cox-Budlong House |
| Cox Building |
| Cox Farmhouse |
| Cox, Gardner, House |
| Cox, Isaac, Cobblestone Farmstead |
| Cox, Richard, House |
| Crabtree, John A., House |
| Cragsmoor Historic District |
| Cragston Dependencies |
| Cramer, Frederick, House |
| Crandall Farm Complex |
| Crandall Marine Railway |
| Crandell Theatre |
| Crane, Gerard, House |
| Crane House |
| Craver Farmstead |
| Crawford, David, House |
| Crawford, John I, Farm |
| Creek Meeting House and Friends' Cemetery |
| Crego, Mrs.. I.L., House |
| Crescent Corset Company |
| Crescent Methodist Episcopal Church |
| Crest, The |
| Crest, The |
| Cromwell Manor |
| Cronkite, Jeremiah, House |
| Cronyn, William B., House |
| Crooked Lake Outlet Historic District |
| Crosman Terrace Historic District |
| Crossover Island Light Station |
| Croswell-Parsons Paper Mill Ruin |
| Crotona Play Center |
| Croton Aqueduct Gate House |
| Croton North Railroad Station |
Data from United States Park Service and Wikidata
