| Wealdstone to Orbetello | 832.34 mi (1,339.52 km) |
| Wealdstone to Oria | 1,147.71 mi (1,847.05 km) |
| Wealdstone to Oristano | 913.63 mi (1,470.35 km) |
| Wealdstone to Orta Nova | 1,038.03 mi (1,670.54 km) |
| Wealdstone to Orte | 867.86 mi (1,396.69 km) |
| Wealdstone to Ortona | 940.54 mi (1,513.65 km) |
| Wealdstone to Orvieto | 845.18 mi (1,360.19 km) |
| Wealdstone to Orzinuovi | 634.75 mi (1,021.54 km) |
| Wealdstone to Osimo | 851.66 mi (1,370.62 km) |
| Wealdstone to Ospitaletto | 631.84 mi (1,016.84 km) |
| Wealdstone to Ostuni | 1,134.02 mi (1,825.03 km) |
| Wealdstone to Ottaviano | 1,022.20 mi (1,645.07 km) |
| Wealdstone to Ovada | 633.62 mi (1,019.71 km) |
| Wealdstone to Ozieri | 881.00 mi (1,417.84 km) |
| Wealdstone to Paceco | 1,129.38 mi (1,817.57 km) |
