| Middelkerke to Oria | 1,022.64 mi (1,645.79 km) |
| Middelkerke to Oristano | 827.19 mi (1,331.24 km) |
| Middelkerke to Orta Nova | 915.43 mi (1,473.25 km) |
| Middelkerke to Orte | 752.29 mi (1,210.70 km) |
| Middelkerke to Ortona | 818.44 mi (1,317.15 km) |
| Middelkerke to Orvieto | 729.69 mi (1,174.31 km) |
| Middelkerke to Orzinuovi | 515.93 mi (830.32 km) |
| Middelkerke to Osimo | 728.29 mi (1,172.08 km) |
| Middelkerke to Ospitaletto | 511.51 mi (823.19 km) |
| Middelkerke to Ostuni | 1,008.48 mi (1,622.99 km) |
| Middelkerke to Ottaviano | 904.79 mi (1,456.11 km) |
| Middelkerke to Ovada | 526.26 mi (846.94 km) |
| Middelkerke to Ozieri | 789.77 mi (1,271.01 km) |
| Middelkerke to Paceco | 1,028.11 mi (1,654.59 km) |
| Middelkerke to Pachino | 1,168.00 mi (1,879.72 km) |
