Pennsylvania - Criteria: A (event)
| Cheyney, Squire, Farm |
| Chichester Friends Meetinghouse |
| Chickies Historic District |
| Christ Hamilton United Lutheran Church and Cemetery |
| Christman, Philip, House |
| Church Farm School Historic District |
| Church Hill Farm |
| Citizens National Bank of Latrobe |
| City Hall |
| City Park Brewery |
| Clarion County Courthouse and Jail |
| Clark, Silas M., House |
| Clarkson-Watson House |
| Class and Nachod Brewery |
| Clear Creek State Park Day Use District |
| Clear Creek State Park Family Cabin District |
| Clearfield Armory |
| Clearfield County Courthouse |
| Clear Spring Mill |
| Clinger-Moses Mill Complex |
| Cliveden (Chew House) |
| Coalport Historic District |
| Coates, Moses, Jr., Farm |
| Coatesville Historic District |
| Coatesville Veterans Administration Hospital Historic District |
| Cobbs Creek Automobile Suburb Historic District |
| Codorus Forge and Furnace Historic District |
| Coffeetown Grist Mill |
| Cogan House Covered Bridge |
| Cold Point Historic District |
| Cold Spring Farm |
| Cold Spring Farm Springhouse |
| Colebrook Manor |
| Colemanville Covered Bridge |
| Colerain Forges Mansion |
| Cole, Warren Z., House |
| Colfax Elementary School |
| College Hall, University Of Pennsylvania |
| College Heights Historic District |
| College Hill Residential Historic District |
| College of Physicians of Philadelphia Building |
| Colley, Abel, Tavern |
| Colley, Peter, Tavern and Barn |
| Colonial Germantown Historic District |
| Colonial Theatre |
| Colton Point State Park |
| Columbia Historic District |
| Columbia Wagon Works |
| Colver Historic District |
| Commandant's Quarters |
| Commercial Hotel |
| Commodore Historic District |
| Compass Inn |
| Compton and Bloomfield |
| Concord Friends Meetinghouse |
| Concordville Historic District |
| Conestoga Cork Works Building |
| Conewago Chapel |
| Congregational Store |
| Connellsville Armory |
| Connellsville Union Passenger Depot |
| Connelly, Clifford B., Trade School |
| Conroy Junior High School |
| Consolidated Ice Company Factory No. 2 |
| Consolidation Freight Locomotive No. 1187 |
| Consolidation Freight Locomotive No. 2846 |
| Consolidation Freight Locomotive No. 7688 |
| Consumers Cigar Box Company |
| Continental Stove Works |
| Conwell, Russell H., School |
| Cooke, Jay, Junior High School |
| Cookes House |
| Cook Forest State Park Indian Cabin District |
| Cook Forest State Park River Cabin District |
| Coopersburg Historic District |
| Cope's Bridge |
| Coraopolis Armory |
| Coraopolis Bridge |
| Coraopolis Railroad Station |
| Cornwall Iron Furnace |
| Cornwall & Lebanon Railroad Station |
| Corry Armory |
| Cotton and Maple Streets School |
| Coudersport and Port Allegany Railroad Station |
| Coudersport Historic District |
| Coulsontown Cottages Historic District |
| Coventry Hall |
| Coventryville Historic District |
| Cowans Gap State Park Family Cabin District |
| Crawford Covered Bridge |
| Creasyville Covered Bridge |
| Cressbrook Farm |
| Crook Farm |
| Crosley-Garrett Mill Workers' Housing, Store and Mill Site |
| Culbertson-Harbison Farm |
| Cumberland Valley Railroad Station and Station Master's House |
| Cumberland Valley State Normal School Historic District |
| Cuppett's Covered Bridge |
| Curtis Arboretum |
| Cuttalossa Valley Historic District |
Data from United States Park Service and Wikidata
