| Castel Bolognese to Octeville | 730.78 mi (1,176.08 km) |
| Castel Bolognese to Oignies | 591.15 mi (951.36 km) |
| Castel Bolognese to Oissel | 612.93 mi (986.42 km) |
| Castel Bolognese to Olivet | 533.37 mi (858.38 km) |
| Castel Bolognese to Ollioules | 308.08 mi (495.81 km) |
| Castel Bolognese to Olonne-sur-Mer | 674.87 mi (1,086.09 km) |
| Castel Bolognese to Oloron-Sainte-Marie | 623.39 mi (1,003.26 km) |
| Castel Bolognese to Onet Village | 454.71 mi (731.78 km) |
| Castel Bolognese to Onnaing | 567.98 mi (914.07 km) |
| Castel Bolognese to Orange | 346.21 mi (557.17 km) |
| Castel Bolognese to Orchies | 583.35 mi (938.82 km) |
| Castel Bolognese to Orleans | 534.10 mi (859.54 km) |
| Castel Bolognese to Orly | 541.16 mi (870.91 km) |
| Castel Bolognese to Ormesson-sur-Marne | 537.00 mi (864.22 km) |
| Castel Bolognese to Orsay | 547.63 mi (881.32 km) |
