Pennsylvania - Criteria: C (architecture/engineering)
| 109-115 Wood Street |
| 1616 Building |
| 1724 Chester Courthouse |
| 1900 Rittenhouse Square Apartments |
| 26th District Police and Patrol Station |
| 32nd St. and Lancaster Ave. Philadelphia Armory |
| Aaronsburg Historic District |
| Abbeville |
| Abbott, John, House |
| Abington Township High School |
| Academy Hall |
| Academy Hill Historic District |
| Academy Hill Historic District |
| Academy of Music |
| Adams Avenue Bridge in Philadelphia |
| Adams, C.F., Building |
| Adams County Courthouse |
| Adamson, William, School |
| Adelphi School |
| Ad-Lin Building |
| Administration Building, Washington and Jefferson College |
| Albertson, Henry, Subdivision Historic District |
| Albright Memorial Building |
| Alcorn, James, School |
| Alden Park Manor |
| Alden Villa |
| Alfred Newton Richards Medical Research Laboratories and David Goddard Laboratories Buildings |
| Alleghany Mennonite Meetinghouse |
| Allegheny Aqueduct |
| Allegheny Baptist Church |
| Allegheny Cemetery |
| Allegheny County Courthouse and Jail |
| Allegheny High School |
| Allegheny Observatory |
| Allegheny Portage Railroad National Historic Site |
| Allegheny Post Office |
| Allegheny River Locka and Dam No. 5 |
| Allegheny River Lock and Dam No. 2 |
| Allegheny River Lock and Dam No. 3 |
| Allegheny River Lock and Dam No. 4 |
| Allegheny River Lock and Dam No. 6 |
| Allegheny River Lock and Dam No. 7 |
| Allegheny River Lock and Dam No.8 |
| Allegheny River Lock and Dam No. 9 |
| Allegheny West Historic District |
| Allen, Ethan, School |
| Allentown Masonic Temple |
| Allentown National Bank |
| Allenwood River Bridge |
| Allerdice, Taylor, High School |
| Allerman, Conrad and Margaret, House |
| Allgates |
| Allison, William, House |
| Alpha Terrace Historic District |
| Altoona Armory |
| Ambridge Commercial Historic District |
| American Baptist Publication Society |
| American/Consolidated Tobacco Companies |
| American Railway Express Company Garage |
| Americus Hotel |
| Andrews Bridge Historic District |
| Anglecot, The |
| Angle Farm |
| Annville Historic District |
| Anoatok |
| Antes, Henry, House |
| Anthracite Bank Building |
| Arch Street Friends Meeting House |
| Arch Street Opera House |
| Arch Street Presbyterian Church |
| Armstrong Cork Company |
| Armstrong Tunnel |
| Arndt, Jacob, House and Barn |
| Arsenal Junior High School |
| Ashbridge, David, Log House |
| Ashley and Bailey Company Silk Mill |
| Ashley and Bailey Silk Mill |
| Ashley Planes |
| Ashton-Hursh House |
| Askew Bridge |
| Athenaeum of Philadelphia |
| Athens Historic District |
| Atkinson Road Bridge |
| Audenried, Charles Y., Junior High School |
| Augustus Lutheran Church |
| Autun |
| Awbury Historic District |
| Axe, William W., School |
| Ayres, Bucher, Farm |
| Ayres, John, House |
| Bache, Alexander Dallas, School |
| Bachman and Forry Tobacco Warehouse |
| Bahr Mill Complex |
| Bailey, John, Farm |
| Baily Farm |
| Baird, Matthew, Mansion |
| Bair, Oliver, H., Funeral Home |
| Baker Bridge |
| Baker Mansion |
| Baldwin-Reynolds House |
Data from United States Park Service and Wikidata
