Oregon - Area of significance: Architecture
| Abraham, Simon, Duplex |
| Acorn Woman Peak Lookout |
| Adams, Charles F., House |
| Adams, Louise, House |
| Adams, Louis J., House |
| Adams Odd Fellows Hall |
| Administration Building |
| Adolph Block |
| Adolph, Samuel, House |
| Advent Christian Church |
| Aegerter, David and Maggie, Barn |
| Ahlf, John and Susanna, House |
| Ahlstrom, Nils, House |
| Ainsworth, Capt. John C., House |
| Ainsworth, Maud and Belle, House |
| Albany Custom Mill |
| Albany Downtown Commercial Historic District |
| Albany Municipal Airport |
| Albee, H. Russell, House |
| Albright, Daniel, Farm |
| Alger Theatre |
| Allison Ranger Station |
| Aloha Farmhouse |
| Alphabet Historic District |
| Alpha Phi Sorority House |
| Alpha Tau Omega Fraternity House (Old) |
| Ambassador Apartments |
| Ambruster, Frederick, Cottage |
| American Apartment Building |
| Amundsen, Roy E. and Hildur L., House |
| Anderson, Emanuel and Christina, House |
| Anderson, James Mechlin, House |
| Anderson, Lewis, House, Barn and Granary |
| Anderson, Thomas N., House |
| Andrus, Jerry, House |
| Annand-Loomis House |
| Antelope School |
| Anthony-Buckley House |
| Anthony, Herman, Farm |
| Anthony, John, House |
| Antlers Guard Station |
| Applegate, Charles, House |
| Archibald, Steven and Elizabeth, Farmstead |
| Arlington Club |
| Arminius Hotel |
| Armstrong, Alfred J. and Georgia A., House |
| Arnold-Park Log Home |
| Ascension Episcopal Church and Rectory |
| Ashland Downtown Historic District |
| Ashland Oregon National Guard Armory |
| Ashley, Mark A. M., House |
| Astor Building |
| Astoria City Hall |
| Astoria Column |
| Astoria Downtown Historic District |
| Astoria Elks Building |
| Astoria Fire House No. 2 |
| Astoria Wharf and Warehouse Company |
| Astor, John Jacob, Hotel |
| Atkinson, W. H., House |
| Auditorium and Music Hall |
| Aurora Colony Historic District |
| Auto Rest Garage |
| Autzen, Thomas J., House |
| Avery-Helm Historic District |
| Avery House |
| Ax Billy Department Store |
| Ayer-Shea House |
| Ayer, W. B., House |
| Babcock, Charles C., House |
| Baber, Granville H., House |
| Bader, Louis J., House and Garden |
| Bagby Guard Station |
| Bagdad Theatre |
| Bailey and Massingill Store |
| Bailey, Lawrence D., House |
| Baker, Hiram, House |
| Baker Historic District |
| Baker, Horace, Log Cabin |
| Baker Municipal Natatorium |
| Baker, Sophenia Ish, House |
| Baldwin Hotel |
| Baldwin Market |
| Baldwin, Thomas M., House |
| Balfour-Gutherie Building |
| Ball, Abraham and Phoebe, House |
| Ball-Ehrman House |
| Ballou & Wright Company Building |
| Bank of California Building |
| Bank of Echo Building |
| Bank of Woodburn |
| Barber Block |
| Barclay, Dr. Forbes, House |
| Barclay-Klum House |
| Barker, S. B., Building |
| Barlow, William, House |
| Barnard, Dr. J. W., Building and First National Bank of Joseph |
| Barnes, Frank C., House |
| Barnhart-Wright House |
| Barnum Hotel |
Data from United States Park Service and Wikidata
