| Pen-y-Bont ar Ogwr to Opwijk | 337.67 mi (543.43 km) |
| Pen-y-Bont ar Ogwr to Ostend | 280.88 mi (452.03 km) |
| Pen-y-Bont ar Ogwr to Oud-Heverlee | 360.02 mi (579.40 km) |
| Pen-y-Bont ar Ogwr to Oud-Turnhout | 368.99 mi (593.83 km) |
| Pen-y-Bont ar Ogwr to Oudenaarde | 314.09 mi (505.48 km) |
| Pen-y-Bont ar Ogwr to Oudenburg | 284.69 mi (458.17 km) |
| Pen-y-Bont ar Ogwr to Oupeye | 403.55 mi (649.45 km) |
| Pen-y-Bont ar Ogwr to Overijse | 354.96 mi (571.25 km) |
| Pen-y-Bont ar Ogwr to Overpelt | 388.34 mi (624.97 km) |
| Pen-y-Bont ar Ogwr to Paal | 379.42 mi (610.62 km) |
| Pen-y-Bont ar Ogwr to Peer | 390.62 mi (628.64 km) |
| Pen-y-Bont ar Ogwr to Pepinster | 413.03 mi (664.71 km) |
| Pen-y-Bont ar Ogwr to Peruwelz | 318.62 mi (512.76 km) |
| Pen-y-Bont ar Ogwr to Perwez | 369.30 mi (594.33 km) |
| Pen-y-Bont ar Ogwr to Philippeville | 365.66 mi (588.47 km) |
