| Willoughby to Opwijk | 3,901.75 mi (6,279.26 km) |
| Willoughby to Ostend | 3,844.64 mi (6,187.35 km) |
| Willoughby to Oud-Heverlee | 3,924.71 mi (6,316.21 km) |
| Willoughby to Oud-Turnhout | 3,921.81 mi (6,311.55 km) |
| Willoughby to Oudenaarde | 3,882.61 mi (6,248.46 km) |
| Willoughby to Oudenburg | 3,849.06 mi (6,194.46 km) |
| Willoughby to Oupeye | 3,966.58 mi (6,383.59 km) |
| Willoughby to Overijse | 3,921.09 mi (6,310.38 km) |
| Willoughby to Overpelt | 3,941.64 mi (6,343.46 km) |
| Willoughby to Paal | 3,937.84 mi (6,337.35 km) |
| Willoughby to Peer | 3,945.72 mi (6,350.02 km) |
| Willoughby to Pepinster | 3,977.86 mi (6,401.75 km) |
| Willoughby to Peruwelz | 3,892.22 mi (6,263.92 km) |
| Willoughby to Perwez | 3,937.07 mi (6,336.10 km) |
| Willoughby to Philippeville | 3,940.12 mi (6,341.01 km) |
