| Castellamonte to Opwijk | 418.60 mi (673.67 km) |
| Castellamonte to Ostend | 459.71 mi (739.83 km) |
| Castellamonte to Oud-Heverlee | 401.91 mi (646.81 km) |
| Castellamonte to Oud-Turnhout | 428.69 mi (689.90 km) |
| Castellamonte to Oudenaarde | 422.58 mi (680.08 km) |
| Castellamonte to Oudenburg | 455.41 mi (732.91 km) |
| Castellamonte to Oupeye | 380.18 mi (611.84 km) |
| Castellamonte to Overijse | 400.90 mi (645.19 km) |
| Castellamonte to Overpelt | 416.66 mi (670.55 km) |
| Castellamonte to Paal | 407.92 mi (656.48 km) |
| Castellamonte to Peer | 410.65 mi (660.87 km) |
| Castellamonte to Pepinster | 368.77 mi (593.47 km) |
| Castellamonte to Peruwelz | 402.80 mi (648.25 km) |
| Castellamonte to Perwez | 386.08 mi (621.34 km) |
| Castellamonte to Philippeville | 363.73 mi (585.37 km) |
