| Castel Gandolfo to Opwijk | 753.14 mi (1,212.05 km) |
| Castel Gandolfo to Ostend | 800.57 mi (1,288.39 km) |
| Castel Gandolfo to Oud-Heverlee | 733.53 mi (1,180.50 km) |
| Castel Gandolfo to Oud-Turnhout | 754.07 mi (1,213.56 km) |
| Castel Gandolfo to Oudenaarde | 761.86 mi (1,226.09 km) |
| Castel Gandolfo to Oudenburg | 796.09 mi (1,281.19 km) |
| Castel Gandolfo to Oupeye | 703.25 mi (1,131.77 km) |
| Castel Gandolfo to Overijse | 733.99 mi (1,181.23 km) |
| Castel Gandolfo to Overpelt | 738.48 mi (1,188.46 km) |
| Castel Gandolfo to Paal | 733.45 mi (1,180.37 km) |
| Castel Gandolfo to Peer | 732.67 mi (1,179.12 km) |
| Castel Gandolfo to Pepinster | 690.95 mi (1,111.97 km) |
| Castel Gandolfo to Peruwelz | 744.27 mi (1,197.78 km) |
| Castel Gandolfo to Perwez | 717.93 mi (1,155.40 km) |
| Castel Gandolfo to Philippeville | 700.85 mi (1,127.91 km) |
