| Olesa de Montserrat to Orbetello | 482.23 mi (776.08 km) |
| Olesa de Montserrat to Oria | 822.45 mi (1,323.61 km) |
| Olesa de Montserrat to Oristano | 368.40 mi (592.88 km) |
| Olesa de Montserrat to Orta Nova | 715.07 mi (1,150.80 km) |
| Olesa de Montserrat to Orte | 542.03 mi (872.32 km) |
| Olesa de Montserrat to Ortona | 644.46 mi (1,037.16 km) |
| Olesa de Montserrat to Orvieto | 529.36 mi (851.93 km) |
| Olesa de Montserrat to Orzinuovi | 482.77 mi (776.94 km) |
| Olesa de Montserrat to Osimo | 604.67 mi (973.13 km) |
| Olesa de Montserrat to Ospitaletto | 494.10 mi (795.18 km) |
| Olesa de Montserrat to Ostuni | 817.17 mi (1,315.11 km) |
| Olesa de Montserrat to Ottaviano | 655.36 mi (1,054.70 km) |
| Olesa de Montserrat to Ovada | 402.00 mi (646.95 km) |
| Olesa de Montserrat to Ozieri | 376.11 mi (605.29 km) |
| Olesa de Montserrat to Paceco | 616.55 mi (992.25 km) |
