Pennsylvania - Criteria: C (architecture/engineering)
| Seventh Street Bridge |
| Seville Theatre |
| Sewickley Manor |
| Seyfert Mill |
| Seymour, Edward B., House |
| Shade Gap Feed and Flour Mill |
| Shadyside Presbyterian Church |
| Shaffer's Bridge |
| Sharples Homestead |
| Sharpless Homestead |
| Sharpless, William C., House |
| Sharswood, George, School |
| Shaw, Anna Howard, Junior High School |
| Shaw Historic District |
| Sheads House |
| Sheard, Levi, Mill |
| Sheard's Mill Covered Bridge |
| Shearer's Covered Bridge |
| Shedwick, John, Development Houses |
| Sheffield Apartments |
| Shelly School |
| Shelly, William, School and Annex |
| Shelter House |
| Shenk's Mill Covered Bridge |
| Sheridan, Philip H., School |
| Sherman, L. G., Tobacco Warehouse |
| Shields, David, House |
| Ship Inn |
| Shippen House |
| Shippen, Judge Henry, House |
| Shippensburg Historic District |
| Shoaf Historic District |
| Shoemaker, Capt. Jacob, House |
| Shoemaker Covered Bridge |
| Shoemaker, William, Junior High School |
| Shreiner Farm |
| Shrewsbury Historic District |
| Shrewsbury Railroad Station, Stewartstown Railroad |
| Siegfried's Dale Farm |
| Silkman House |
| Silver Lake Bank |
| Simon, Herman, House |
| Simpson Street School |
| Singer, John F., House |
| Sinking Springs Farms |
| Sinnott, Joseph, Mansion |
| Sixteenth Street Bridge |
| Sixth Street Bridge |
| Skinner Tavern |
| Skippack Bridge |
| Slater Cigar Company |
| Slatington Historic District |
| Sleepy Hollow Hall |
| Slickville Historic District |
| Slifer House |
| Smalley, Lewis, Homestead |
| Smaltz Building |
| Smedley, Franklin, School |
| Smith Family Farmstead |
| Smithfield Street Bridge |
| Smith, Henry, Farm |
| Smith, Walter George, School |
| Smith, William, House |
| Smock Historic District |
| Smyser and English Pharmacy |
| Snellenburg's Clothing Factory |
| Snooks Covered Bridge |
| Snyder, Caspar, House |
| Snyder Covered Bridge No. 17 |
| Snyder, Gov. Simon, Mansion |
| Snyder Mill |
| Snyder, William Penn, House |
| Social Service Building |
| Society Hill Historic District |
| Sodom Schoolhouse |
| Soldiers and Sailors Memorial Bridge |
| Soldiers and Sailors Memorial Hall |
| Soldiers and Sailors Monument |
| Solitude Farm |
| Solomon House |
| Somerset County Courthouse |
| Sotcher Farmhouse |
| Southampton Baptist Church and Cemetery |
| South Bethlehem Downtown Historic District |
| South Brook Farm |
| South Fork Fishing and Hunting Club Historic District |
| South Front Street Historic District |
| South, George W., Memorial Protestant Episcopal Church of the Advocate |
| South Perkasie Covered Bridge |
| South Road Bridge, Northern Central Railway |
| South Side High School |
| South Side Market Building |
| South Tenth Street Bridge |
| South Ward School |
| Southwark District |
| Southwark School |
| South Wayne Historic District |
| Spalding Memorial Library-Tioga Point Museum |
| Spannuth Mill |
| Speakman No. 1 |
Data from United States Park Service and Wikidata
