| Ostrow Mazowiecka to Noventa Vicentina | 698.76 mi (1,124.54 km) |
| Ostrow Mazowiecka to Novi di Modena | 739.02 mi (1,189.34 km) |
| Ostrow Mazowiecka to Novi Ligure | 813.28 mi (1,308.84 km) |
| Ostrow Mazowiecka to Nuoro | 1,045.70 mi (1,682.89 km) |
| Ostrow Mazowiecka to Occhiobello | 717.13 mi (1,154.10 km) |
| Ostrow Mazowiecka to Oderzo | 643.08 mi (1,034.94 km) |
| Ostrow Mazowiecka to Oggiono | 743.05 mi (1,195.82 km) |
| Ostrow Mazowiecka to Olbia | 1,005.58 mi (1,618.33 km) |
| Ostrow Mazowiecka to Oleggio | 776.48 mi (1,249.63 km) |
| Ostrow Mazowiecka to Olgiate Comasco | 756.13 mi (1,216.88 km) |
| Ostrow Mazowiecka to Olgiate Olona | 766.29 mi (1,233.22 km) |
| Ostrow Mazowiecka to Omegna | 771.02 mi (1,240.84 km) |
| Ostrow Mazowiecka to Opera | 767.37 mi (1,234.96 km) |
| Ostrow Mazowiecka to Oppeano | 708.50 mi (1,140.22 km) |
| Ostrow Mazowiecka to Orbassano | 843.16 mi (1,356.94 km) |
