California - Significance region: Local
| Ramos, John, Sherry House-Depot Saloon |
| Ramsay-Durfee Estate |
| Rancho Canada de los Osos y Pecho y Islay |
| Rancho El Encino |
| Rancho Las Palmas |
| Rancho San Lucas |
| Rankin Building |
| Rattlesnake Canyon Bridge |
| Raymond-Summit Historic District |
| Reading Adobe Site |
| Rectory, Catholic Church of the Assumption |
| Red Dog Townsite |
| Redlands Santa Fe Depot District |
| Redman House |
| Redondo Beach Original Townsite Historic District |
| Redondo Beach Public Library |
| Redwood City Historic Commercial Buildings |
| Redwood City Woman’s Club |
| Redwood Meadow Ranger Station |
| Reedley National Bank |
| Reedley Opera House Complex |
| Rehorn House |
| Remar Bakery |
| Rengstorff, Henry A., House |
| RENOWN (yacht) |
| Renwick, Helen Goodwin, House |
| Renzel, Ernest & Emily, House |
| Republic Cafe |
| Rhine House |
| Rialto Building |
| Rialto Theatre |
| Ricks, Thomas F., House |
| Ridgewood Place Historic District |
| Rindge, Frederick Hastings, House |
| Rispin Mansion |
| Riverbank Branch Library |
| Riverside-Arlington Heights Fruit Exchange |
| Riverside Municipal Auditorium and Soldier's Memorial Building |
| Riverview Union High School Building |
| Rives, James C., House |
| Riviera Gardens |
| ROBERT GRAY (hydrographic survey vessel) |
| Robinson, Elias H., House |
| Robinson Hotel |
| Robinson, Virginia, Estate |
| Robles, Paso, Carnegie Library |
| Rock Tank Corral |
| Rockwell Field |
| Rodgers, Moses, House |
| Rodgers, Patrick, Farm |
| Roma Bakery |
| Romain, Frank, House |
| Ronda |
| Roop's Fort |
| Roosevelt Building |
| Roos House |
| Rosebud Ranch |
| Rose Court |
| Rosecroft |
| Rosenburg's Department Store |
| Ross House |
| Rovegno, Charles, House |
| Rowland, John A., House |
| Royal Laundry Complex |
| Royal Theater |
| Roybal, Edward, House |
| Rozas House |
| Rubel Castle Historic District |
| Ruhstaller Building |
| Ruiz-Alvarado Ranch Site |
| Rumsey Town Hall |
| Runyon House |
| Russian Hill-Macondray Lane District |
| Russian Hill-Paris Block Architectural District |
| Russian Village District |
| Ryan Historic District |
| Ryan House and Lost Horse Well |
| Sachse Spring Snow Survey Shelter |
| Sacramento Bank Building |
| Sacramento City Library |
| Sacramento Hall of Justice |
| Sacramento Junior College Annex and Extensions |
| Sacramento Masonic Temple |
| Sacramento Memorial Auditorium |
| Sacramento Northern Railway Historic District |
| Sacred Heart Catholic Church |
| Sacred Heart Parish Complex |
| Saint Helena Southern Pacific Railroad Depot |
| Saint John's Presbyterian Church |
| Saint Mary's Parish |
| Saint Paul African Methodist Episcopal Church, Santa Barbara |
| Saint Vincent's Hill Historic District |
| San Antonio Heights Grove House |
| San Bernardino County Court House |
| San Clemente Beach Club |
| Sandcliff |
| Sand Hill Bluff Site |
| San Diego Armed Services YMCA |
| San Diego Athletic Club |
| San Diego Civic Center |
Data from United States Park Service and Wikidata
