| Diamond Bar to Oakley (California) | 350.87 mi (564.67 km) |
| Diamond Bar to Oakton (Virginia) | 2,258.37 mi (3,634.50 km) |
| Diamond Bar to Oakville (Missouri) | 1,557.03 mi (2,505.79 km) |
| Diamond Bar to Oatfield (Oregon) | 828.07 mi (1,332.64 km) |
| Diamond Bar to Ocala (Florida) | 2,114.61 mi (3,403.13 km) |
| Diamond Bar to Ocean Acres (New Jersey) | 2,414.89 mi (3,886.39 km) |
| Diamond Bar to Ocean City (New Jersey) | 2,400.57 mi (3,863.35 km) |
| Diamond Bar to Ocean Pines (Maryland) | 2,377.21 mi (3,825.75 km) |
| Diamond Bar to Ocean Pointe (Hawaii) | 2,592.95 mi (4,172.96 km) |
| Diamond Bar to Ocean Springs (Mississippi) | 1,709.45 mi (2,751.09 km) |
| Diamond Bar to Oceanside (California) | 60.97 mi (98.12 km) |
| Diamond Bar to Oceanside (New York) | 2,444.37 mi (3,933.84 km) |
| Diamond Bar to Ocoee (Florida) | 2,163.31 mi (3,481.51 km) |
| Diamond Bar to Oconomowoc (Wisconsin) | 1,693.75 mi (2,725.82 km) |
| Diamond Bar to Odenton (Maryland) | 2,290.03 mi (3,685.44 km) |
