| Dollis Hill to Orbetello | 827.73 mi (1,332.10 km) |
| Dollis Hill to Oria | 1,142.90 mi (1,839.32 km) |
| Dollis Hill to Oristano | 909.51 mi (1,463.72 km) |
| Dollis Hill to Orta Nova | 1,033.24 mi (1,662.84 km) |
| Dollis Hill to Orte | 863.17 mi (1,389.14 km) |
| Dollis Hill to Ortona | 935.76 mi (1,505.96 km) |
| Dollis Hill to Orvieto | 840.49 mi (1,352.63 km) |
| Dollis Hill to Orzinuovi | 630.00 mi (1,013.88 km) |
| Dollis Hill to Osimo | 846.87 mi (1,362.90 km) |
| Dollis Hill to Ospitaletto | 627.06 mi (1,009.16 km) |
| Dollis Hill to Ostuni | 1,129.21 mi (1,817.29 km) |
| Dollis Hill to Ottaviano | 1,017.48 mi (1,637.48 km) |
| Dollis Hill to Ovada | 629.03 mi (1,012.32 km) |
| Dollis Hill to Ozieri | 876.77 mi (1,411.03 km) |
| Dollis Hill to Paceco | 1,124.97 mi (1,810.47 km) |
