Cities, Towns, Neighborhoods & Other Populated Places in California.
| City Name | Title | County | Population |
|---|---|---|---|
| Riverside | County seat of Riverside County, California, United States | Riverside | 331,360 |
| Rancho Cucamonga | Suburban city in San Bernardino County, California | San Bernardino | 177,603 |
| Roseville | City in Placer County, California, United States | Placer | 141,500 |
| Richmond | City in Contra Costa County, California, United States | Contra Costa | 110,567 |
| Rialto | City in California, United States of America | San Bernardino | 103,526 |
| Redding | City in Shasta County, California, United States | Shasta | 92,590 |
| Redwood City | City in California, United States of America | San Mateo | 85,925 |
| Rancho Cordova | City in California | Sacramento | 75,087 |
| Redlands | City in San Bernardino County, California, United States | San Bernardino | 71,513 |
| Rocklin | City in California | Placer | 68,823 |
| Redondo Beach | City in Los Angeles County, California, United States | Los Angeles | 66,749 |
| Rosemead | City in Los Angeles County, California, United States | Los Angeles | 54,058 |
| Rancho Santa Margarita | City in Orange County, California, United States | Orange | 47,896 |
| Rohnert Park | City in California | Sonoma | 43,291 |
| Rancho Palos Verdes | City in Los Angeles County, California, United States | Los Angeles | 41,530 |
| Ridgecrest | City in California | Kern | 28,973 |
| Reedley | City in Fresno County, California, United States | Fresno | 25,658 |
| Riverbank | City in Stanislaus County, California, United States | Stanislaus | 24,881 |
| Rancho Mirage | City in Riverside County, California | Riverside | 18,528 |
| Ripon | City in California | San Joaquin | 16,386 |
| Red Bluff | County seat of Tehama County, California, United States | Tehama | 14,539 |
| Rio Vista | City in Solano County, California, United States of America | Soroti District | 9,718 |
| Rolling Hills Estates | City in Los Angeles County, California, United States | Los Angeles | 8,058 |
| Rancho Calaveras | Census-designated place in Calaveras County, California | Calaveras | 5,325 |
| Rio Dell | City in Humboldt County, California, United States of America | Humboldt | 3,363 |
| Rio Dell | Unincorporated community in Sonoma County, California | Sonoma | 3,349 |
| Ross | Town in California | Marin | 2,451 |
| Rolling Hills | City on the Palos Verdes Peninsula, in Los Angeles County | Los Angeles | 1,845 |