| Rapid City to Olympia (Washington) | 970.99 mi (1,562.65 km) |
| Rapid City to Olympia Heights (Florida) | 1,801.50 mi (2,899.24 km) |
| Rapid City to Omaha (Nebraska) | 412.42 mi (663.73 km) |
| Rapid City to On Top of the World Designated Place (Florida) | 1,546.66 mi (2,489.11 km) |
| Rapid City to Onalaska (Wisconsin) | 596.87 mi (960.56 km) |
| Rapid City to Oneida (New York) | 1,374.74 mi (2,212.44 km) |
| Rapid City to Oneonta (New York) | 1,414.02 mi (2,275.65 km) |
| Rapid City to Ontario (California) | 1,034.63 mi (1,665.08 km) |
| Rapid City to Ontario (Oregon) | 682.32 mi (1,098.10 km) |
| Rapid City to Opa-locka (Florida) | 1,795.47 mi (2,889.53 km) |
| Rapid City to Opelika (Alabama) | 1,242.62 mi (1,999.80 km) |
| Rapid City to Opelousas (Louisiana) | 1,116.07 mi (1,796.14 km) |
| Rapid City to Orange (California) | 1,054.93 mi (1,697.75 km) |
| Rapid City to Orange (Texas) | 1,093.97 mi (1,760.57 km) |
| Rapid City to Orange City (Florida) | 1,596.30 mi (2,569.00 km) |
