| Rapid City to Orbetello | 5,217.88 mi (8,397.37 km) |
| Rapid City to Oria | 5,535.92 mi (8,909.20 km) |
| Rapid City to Oristano | 5,253.07 mi (8,454.00 km) |
| Rapid City to Orta Nova | 5,427.92 mi (8,735.40 km) |
| Rapid City to Orte | 5,256.99 mi (8,460.31 km) |
| Rapid City to Ortona | 5,330.55 mi (8,578.70 km) |
| Rapid City to Orvieto | 5,234.36 mi (8,423.88 km) |
| Rapid City to Orzinuovi | 5,025.07 mi (8,087.07 km) |
| Rapid City to Osimo | 5,241.06 mi (8,434.67 km) |
| Rapid City to Ospitaletto | 5,022.01 mi (8,082.15 km) |
| Rapid City to Ostuni | 5,521.71 mi (8,886.34 km) |
| Rapid City to Ottaviano | 5,411.81 mi (8,709.47 km) |
| Rapid City to Ovada | 5,019.16 mi (8,077.56 km) |
| Rapid City to Ozieri | 5,233.88 mi (8,423.12 km) |
| Rapid City to Paceco | 5,494.42 mi (8,842.41 km) |
