| Ostend to Oria | 1,021.20 mi (1,643.46 km) |
| Ostend to Oristano | 828.24 mi (1,332.92 km) |
| Ostend to Orta Nova | 914.22 mi (1,471.29 km) |
| Ostend to Orte | 751.66 mi (1,209.68 km) |
| Ostend to Ortona | 817.28 mi (1,315.29 km) |
| Ostend to Orvieto | 729.06 mi (1,173.32 km) |
| Ostend to Orzinuovi | 515.17 mi (829.09 km) |
| Ostend to Osimo | 727.06 mi (1,170.09 km) |
| Ostend to Ospitaletto | 510.62 mi (821.77 km) |
| Ostend to Ostuni | 1,007.00 mi (1,620.60 km) |
| Ostend to Ottaviano | 903.97 mi (1,454.80 km) |
| Ostend to Ovada | 526.31 mi (847.01 km) |
| Ostend to Ozieri | 790.58 mi (1,272.32 km) |
| Ostend to Paceco | 1,028.31 mi (1,654.90 km) |
| Ostend to Pachino | 1,167.77 mi (1,879.35 km) |
