| Romanshorn to Opwijk | 331.04 mi (532.76 km) |
| Romanshorn to Ostend | 384.22 mi (618.34 km) |
| Romanshorn to Oud-Heverlee | 309.51 mi (498.11 km) |
| Romanshorn to Oud-Turnhout | 325.22 mi (523.39 km) |
| Romanshorn to Oudenaarde | 344.90 mi (555.07 km) |
| Romanshorn to Oudenburg | 379.66 mi (611.00 km) |
| Romanshorn to Oupeye | 274.50 mi (441.76 km) |
| Romanshorn to Overijse | 311.25 mi (500.91 km) |
| Romanshorn to Overpelt | 308.29 mi (496.15 km) |
| Romanshorn to Paal | 305.18 mi (491.14 km) |
| Romanshorn to Peer | 302.69 mi (487.13 km) |
| Romanshorn to Pepinster | 262.11 mi (421.82 km) |
| Romanshorn to Peruwelz | 331.51 mi (533.51 km) |
| Romanshorn to Perwez | 294.74 mi (474.34 km) |
| Romanshorn to Philippeville | 284.29 mi (457.52 km) |
