| Serpa to Opwijk | 1,068.14 mi (1,719.00 km) |
| Serpa to Ostend | 1,051.13 mi (1,691.63 km) |
| Serpa to Oud-Heverlee | 1,073.82 mi (1,728.14 km) |
| Serpa to Oud-Turnhout | 1,108.50 mi (1,783.96 km) |
| Serpa to Oudenaarde | 1,046.53 mi (1,684.23 km) |
| Serpa to Oudenburg | 1,050.60 mi (1,690.78 km) |
| Serpa to Oupeye | 1,094.67 mi (1,761.70 km) |
| Serpa to Overijse | 1,067.48 mi (1,717.95 km) |
| Serpa to Overpelt | 1,114.95 mi (1,794.33 km) |
| Serpa to Paal | 1,098.76 mi (1,768.28 km) |
| Serpa to Peer | 1,111.52 mi (1,788.82 km) |
| Serpa to Pepinster | 1,092.45 mi (1,758.13 km) |
| Serpa to Peruwelz | 1,027.52 mi (1,653.64 km) |
| Serpa to Perwez | 1,066.70 mi (1,716.68 km) |
| Serpa to Philippeville | 1,036.70 mi (1,668.41 km) |
