| Smolyan to Opwijk | 1,168.68 mi (1,880.81 km) |
| Smolyan to Ostend | 1,225.94 mi (1,972.97 km) |
| Smolyan to Oud-Heverlee | 1,145.71 mi (1,843.84 km) |
| Smolyan to Oud-Turnhout | 1,148.70 mi (1,848.65 km) |
| Smolyan to Oudenaarde | 1,188.29 mi (1,912.37 km) |
| Smolyan to Oudenburg | 1,221.55 mi (1,965.90 km) |
| Smolyan to Oupeye | 1,103.73 mi (1,776.28 km) |
| Smolyan to Overijse | 1,149.43 mi (1,849.83 km) |
| Smolyan to Overpelt | 1,128.93 mi (1,816.83 km) |
| Smolyan to Paal | 1,132.48 mi (1,822.55 km) |
| Smolyan to Peer | 1,124.76 mi (1,810.12 km) |
| Smolyan to Pepinster | 1,092.47 mi (1,758.16 km) |
| Smolyan to Peruwelz | 1,179.63 mi (1,898.43 km) |
| Smolyan to Perwez | 1,133.55 mi (1,824.28 km) |
| Smolyan to Philippeville | 1,131.82 mi (1,821.48 km) |
