| Ostend to Obernburg am Main | 289.44 mi (465.81 km) |
| Ostend to Obernkirchen | 274.64 mi (441.99 km) |
| Ostend to Oberschleissheim | 437.08 mi (703.41 km) |
| Ostend to Oberstdorf | 423.21 mi (681.09 km) |
| Ostend to Obertraubling | 438.24 mi (705.29 km) |
| Ostend to Obertshausen | 271.11 mi (436.31 km) |
| Ostend to Oberursel | 257.32 mi (414.11 km) |
| Ostend to Ochsenfurt | 332.67 mi (535.39 km) |
| Ostend to Ochsenhausen | 382.29 mi (615.24 km) |
| Ostend to Ochtrup | 194.92 mi (313.70 km) |
| Ostend to Odenthal | 182.46 mi (293.64 km) |
| Ostend to Oelde | 228.66 mi (368.00 km) |
| Ostend to Oelsnitz | 407.21 mi (655.34 km) |
| Ostend to Oer-Erkenschwick | 188.75 mi (303.76 km) |
| Ostend to Oerlinghausen | 251.86 mi (405.33 km) |
