| Romanshorn to Nuth | 279.61 mi (450.00 km) |
| Romanshorn to Oegstgeest | 386.19 mi (621.52 km) |
| Romanshorn to Oirschot | 327.09 mi (526.41 km) |
| Romanshorn to Oisterwijk | 334.27 mi (537.96 km) |
| Romanshorn to Oldebroek | 370.77 mi (596.69 km) |
| Romanshorn to Oldenzaal | 345.59 mi (556.17 km) |
| Romanshorn to Ommen | 366.17 mi (589.30 km) |
| Romanshorn to Oosterend | 402.85 mi (648.33 km) |
| Romanshorn to Oosterhout | 346.33 mi (557.37 km) |
| Romanshorn to Oosterwolde | 398.54 mi (641.38 km) |
| Romanshorn to Oostzaan | 390.57 mi (628.56 km) |
| Romanshorn to Opmeer | 404.84 mi (651.52 km) |
| Romanshorn to Oss | 337.27 mi (542.78 km) |
| Romanshorn to Oud-Beijerland | 367.84 mi (591.98 km) |
| Romanshorn to Oudenbosch | 352.32 mi (567.00 km) |
