| Grottammare to Opwijk | 714.39 mi (1,149.70 km) |
| Grottammare to Ostend | 765.73 mi (1,232.32 km) |
| Grottammare to Oud-Heverlee | 693.33 mi (1,115.80 km) |
| Grottammare to Oud-Turnhout | 709.67 mi (1,142.11 km) |
| Grottammare to Oudenaarde | 726.42 mi (1,169.06 km) |
| Grottammare to Oudenburg | 761.18 mi (1,225.00 km) |
| Grottammare to Oupeye | 658.97 mi (1,060.51 km) |
| Grottammare to Overijse | 694.71 mi (1,118.03 km) |
| Grottammare to Overpelt | 692.56 mi (1,114.57 km) |
| Grottammare to Paal | 689.65 mi (1,109.89 km) |
| Grottammare to Peer | 687.02 mi (1,105.65 km) |
| Grottammare to Pepinster | 646.58 mi (1,040.57 km) |
| Grottammare to Peruwelz | 711.03 mi (1,144.30 km) |
| Grottammare to Perwez | 678.27 mi (1,091.57 km) |
| Grottammare to Philippeville | 665.17 mi (1,070.49 km) |
