| Twickenham to Orbetello | 825.26 mi (1,328.13 km) |
| Twickenham to Oria | 1,142.01 mi (1,837.88 km) |
| Twickenham to Oristano | 905.03 mi (1,456.51 km) |
| Twickenham to Orta Nova | 1,032.05 mi (1,660.92 km) |
| Twickenham to Orte | 861.21 mi (1,385.99 km) |
| Twickenham to Ortona | 934.53 mi (1,503.99 km) |
| Twickenham to Orvieto | 838.54 mi (1,349.49 km) |
| Twickenham to Orzinuovi | 628.57 mi (1,011.59 km) |
| Twickenham to Osimo | 845.85 mi (1,361.26 km) |
| Twickenham to Ospitaletto | 625.81 mi (1,007.15 km) |
| Twickenham to Ostuni | 1,128.39 mi (1,815.97 km) |
| Twickenham to Ottaviano | 1,015.66 mi (1,634.55 km) |
| Twickenham to Ovada | 626.44 mi (1,008.16 km) |
| Twickenham to Ozieri | 872.66 mi (1,404.40 km) |
| Twickenham to Paceco | 1,121.53 mi (1,804.94 km) |
