| Castel San Giorgio to Opwijk | 864.75 mi (1,391.69 km) |
| Castel San Giorgio to Ostend | 914.28 mi (1,471.39 km) |
| Castel San Giorgio to Oud-Heverlee | 844.32 mi (1,358.80 km) |
| Castel San Giorgio to Oud-Turnhout | 862.51 mi (1,388.07 km) |
| Castel San Giorgio to Oudenaarde | 875.19 mi (1,408.48 km) |
| Castel San Giorgio to Oudenburg | 909.76 mi (1,464.11 km) |
| Castel San Giorgio to Oupeye | 811.64 mi (1,306.21 km) |
| Castel San Giorgio to Overijse | 845.28 mi (1,360.34 km) |
| Castel San Giorgio to Overpelt | 845.96 mi (1,361.44 km) |
| Castel San Giorgio to Paal | 842.20 mi (1,355.38 km) |
| Castel San Giorgio to Peer | 840.30 mi (1,352.34 km) |
| Castel San Giorgio to Pepinster | 799.26 mi (1,286.28 km) |
| Castel San Giorgio to Peruwelz | 858.62 mi (1,381.81 km) |
| Castel San Giorgio to Perwez | 828.98 mi (1,334.11 km) |
| Castel San Giorgio to Philippeville | 813.91 mi (1,309.86 km) |
