| Birkenhead to Orbetello | 999.68 mi (1,608.83 km) |
| Birkenhead to Oria | 1,311.02 mi (2,109.88 km) |
| Birkenhead to Oristano | 1,079.22 mi (1,736.83 km) |
| Birkenhead to Orta Nova | 1,202.50 mi (1,935.24 km) |
| Birkenhead to Orte | 1,034.43 mi (1,664.75 km) |
| Birkenhead to Ortona | 1,105.16 mi (1,778.58 km) |
| Birkenhead to Orvieto | 1,011.74 mi (1,628.24 km) |
| Birkenhead to Orzinuovi | 800.21 mi (1,287.81 km) |
| Birkenhead to Osimo | 1,015.66 mi (1,634.55 km) |
| Birkenhead to Ospitaletto | 796.79 mi (1,282.31 km) |
| Birkenhead to Ostuni | 1,297.05 mi (2,087.41 km) |
| Birkenhead to Ottaviano | 1,188.43 mi (1,912.60 km) |
| Birkenhead to Ovada | 801.10 mi (1,289.24 km) |
| Birkenhead to Ozieri | 1,047.55 mi (1,685.86 km) |
| Birkenhead to Paceco | 1,296.91 mi (2,087.17 km) |
