| Romulus to Orbetello | 4,546.59 mi (7,317.02 km) |
| Romulus to Oria | 4,891.21 mi (7,871.64 km) |
| Romulus to Oristano | 4,538.54 mi (7,304.08 km) |
| Romulus to Orta Nova | 4,777.13 mi (7,688.06 km) |
| Romulus to Orte | 4,593.98 mi (7,393.30 km) |
| Romulus to Ortona | 4,680.58 mi (7,532.67 km) |
| Romulus to Orvieto | 4,572.11 mi (7,358.10 km) |
| Romulus to Orzinuovi | 4,376.90 mi (7,043.94 km) |
| Romulus to Osimo | 4,596.33 mi (7,397.08 km) |
| Romulus to Ospitaletto | 4,376.48 mi (7,043.26 km) |
| Romulus to Ostuni | 4,878.91 mi (7,851.85 km) |
| Romulus to Ottaviano | 4,747.28 mi (7,640.01 km) |
| Romulus to Ovada | 4,354.21 mi (7,007.43 km) |
| Romulus to Ozieri | 4,528.83 mi (7,288.44 km) |
| Romulus to Paceco | 4,788.37 mi (7,706.13 km) |
