| Oud-Heverlee to Oestrich-Winkel | 157.62 mi (253.67 km) |
| Oud-Heverlee to Offenburg | 219.25 mi (352.86 km) |
| Oud-Heverlee to Oftersheim | 200.87 mi (323.27 km) |
| Oud-Heverlee to Ohrdruf | 264.65 mi (425.92 km) |
| Oud-Heverlee to Ohringen | 242.38 mi (390.08 km) |
| Oud-Heverlee to Olbernhau | 378.82 mi (609.66 km) |
| Oud-Heverlee to Olching | 349.21 mi (562.00 km) |
| Oud-Heverlee to Oldenburg | 219.65 mi (353.49 km) |
| Oud-Heverlee to Oldenburg in Holstein | 354.07 mi (569.82 km) |
| Oud-Heverlee to Olfen | 132.33 mi (212.96 km) |
| Oud-Heverlee to Olpe | 138.48 mi (222.87 km) |
| Oud-Heverlee to Olsberg | 169.41 mi (272.63 km) |
| Oud-Heverlee to Oranienburg | 389.26 mi (626.45 km) |
| Oud-Heverlee to Ortenberg | 195.26 mi (314.25 km) |
| Oud-Heverlee to Oschatz | 367.69 mi (591.74 km) |
