| Portland to Opwijk | 5,053.86 mi (8,133.40 km) |
| Portland to Ostend | 5,006.98 mi (8,057.95 km) |
| Portland to Oud-Heverlee | 5,073.64 mi (8,165.23 km) |
| Portland to Oud-Turnhout | 5,054.41 mi (8,134.29 km) |
| Portland to Oudenaarde | 5,045.43 mi (8,119.84 km) |
| Portland to Oudenburg | 5,011.42 mi (8,065.10 km) |
| Portland to Oupeye | 5,105.30 mi (8,216.18 km) |
| Portland to Overijse | 5,073.06 mi (8,164.30 km) |
| Portland to Overpelt | 5,070.88 mi (8,160.79 km) |
| Portland to Paal | 5,074.80 mi (8,167.11 km) |
| Portland to Peer | 5,076.54 mi (8,169.90 km) |
| Portland to Pepinster | 5,117.67 mi (8,236.10 km) |
| Portland to Peruwelz | 5,063.59 mi (8,149.06 km) |
| Portland to Perwez | 5,089.17 mi (8,190.23 km) |
| Portland to Philippeville | 5,106.27 mi (8,217.75 km) |
