| Royston to Orbetello | 845.49 mi (1,360.69 km) |
| Royston to Oria | 1,155.03 mi (1,858.84 km) |
| Royston to Oristano | 933.73 mi (1,502.69 km) |
| Royston to Orta Nova | 1,046.52 mi (1,684.20 km) |
| Royston to Orte | 879.20 mi (1,414.93 km) |
| Royston to Ortona | 949.19 mi (1,527.58 km) |
| Royston to Orvieto | 856.52 mi (1,378.43 km) |
| Royston to Orzinuovi | 644.47 mi (1,037.17 km) |
| Royston to Osimo | 859.66 mi (1,383.48 km) |
| Royston to Ospitaletto | 640.92 mi (1,031.46 km) |
| Royston to Ostuni | 1,141.09 mi (1,836.41 km) |
| Royston to Ottaviano | 1,032.94 mi (1,662.36 km) |
| Royston to Ovada | 647.42 mi (1,041.93 km) |
| Royston to Ozieri | 899.87 mi (1,448.21 km) |
| Royston to Paceco | 1,145.79 mi (1,843.97 km) |
