| Romilly-sur-Seine to Oria | 878.73 mi (1,414.17 km) |
| Romilly-sur-Seine to Oristano | 641.49 mi (1,032.38 km) |
| Romilly-sur-Seine to Orta Nova | 766.67 mi (1,233.84 km) |
| Romilly-sur-Seine to Orte | 591.73 mi (952.30 km) |
| Romilly-sur-Seine to Ortona | 669.21 mi (1,077.00 km) |
| Romilly-sur-Seine to Orvieto | 569.10 mi (915.88 km) |
| Romilly-sur-Seine to Orzinuovi | 363.15 mi (584.43 km) |
| Romilly-sur-Seine to Osimo | 582.52 mi (937.47 km) |
| Romilly-sur-Seine to Ospitaletto | 361.97 mi (582.53 km) |
| Romilly-sur-Seine to Ostuni | 865.76 mi (1,393.30 km) |
| Romilly-sur-Seine to Ottaviano | 746.61 mi (1,201.55 km) |
| Romilly-sur-Seine to Ovada | 355.28 mi (571.77 km) |
| Romilly-sur-Seine to Ozieri | 606.08 mi (975.39 km) |
| Romilly-sur-Seine to Paceco | 851.20 mi (1,369.87 km) |
| Romilly-sur-Seine to Pachino | 997.16 mi (1,604.78 km) |
