All - Constructed - 1850–1859
| 16 Altamont Terrace |
| Absecon Lighthouse |
| Academy of Music |
| Adams County Courthouse |
| Adams Grove Presbyterian Church |
| Administration Building, Lake Erie College |
| Adrian Engine House No. 1 |
| Adsmore |
| African Church |
| Ailes House |
| Ailes, William, House |
| Airmount Grave Shelter |
| Akin, Daniel F., House |
| Albright, Henry D. and Juliana (Wortz), House |
| Alleghany Mennonite Meetinghouse |
| Allen, Abram, House |
| Allen-Beville House |
| Allendale Plantation Historic District |
| Allen Grove |
| Allen House |
| Almshouse |
| Alpine LDS Church Meetinghouse |
| Alston-Cobb House |
| Altaville Grammar School |
| Alverson-Copeland House |
| Ambrose Chapel |
| Ames-Florida House |
| Amis, Jonathan, House |
| Anderson-Coward House |
| Anderson, Mons, House |
| Anderson-Shaffer House |
| Andover Town Hall |
| Andrews, Joseph, House |
| Androscoggin County Courthouse and Jail |
| Angell, Otis, Gristmill |
| Angels Hotel |
| Annefield |
| Annesdale |
| Anthracite Bank Building |
| Antioch Christian Church |
| Antioch Hall, North And South Halls |
| Appellate Court, 5th District |
| Apple, Christopher, House |
| Applegate, Charles, House |
| Aransas Pass Light Station |
| Arbor Lodge |
| Archambault House |
| Arch Street Presbyterian Church |
| Arcola Presbyterian Church |
| Arlington National Cemetery Historic District |
| Armitage |
| Aroostook County Courthouse and Jail |
| Ashe Cottage |
| Ashland Town House |
| Auburndale Congregational Church |
| Aurora Colony Historic District |
| Avery-Helm Historic District |
| Avon Five Arch Bridge |
| Back Creek Presbyterian Church and Cemeterey |
| Badger, Samuel, Monument |
| Bailey, Liberty Hyde, Birthplace |
| Baker, Capt. Seth, Jr., House |
| Bank of Florence |
| Baptist Church |
| Barela-Reynolds House |
| Barlow House |
| Barnard Observatory |
| Barrackville Covered Bridge |
| Barratt House |
| Barton Academy |
| Bashford, Robert M., House |
| Bassett, Edwin, House |
| Bass Harbor Head Light Station |
| Batavia Institute |
| Bates Mill Historic District |
| Battle House Royale |
| Bauman, Augustus and Elizabeth (Huntsberger), House |
| Baumann House |
| Baxter, Capt. Rodney J., House |
| Baxter, Capt. Sylvester, House |
| Baxter, Charles L., House |
| Beacon Street Tomb |
| Beam, Charles Walton, House |
| Beard, Benjamin, House |
| Beard, Padilla, House |
| Bearse, Capt. Allen H., House |
| Beauvoir |
| Beaver Island Light Station |
| Beckwith, Nelson F., House |
| Bedrud-Olson Farmstead |
| Beechland |
| Beehive House |
| Bellamy, Edward, House |
| Bellevue |
| Bellevue |
| Bellevue Mill |
| Bell, John and Margaret, House |
| Belmont |
| Bethany Presbyterian Church |
| Bethel A.M.E. Church |
Data from United States Park Service and Wikidata
