| Gravelines to Oestrich-Winkel | 266.89 mi (429.52 km) |
| Gravelines to Offenburg | 312.19 mi (502.42 km) |
| Gravelines to Oftersheim | 306.62 mi (493.46 km) |
| Gravelines to Ohrdruf | 374.87 mi (603.29 km) |
| Gravelines to Ohringen | 349.14 mi (561.88 km) |
| Gravelines to Olbernhau | 489.09 mi (787.12 km) |
| Gravelines to Olching | 453.94 mi (730.55 km) |
| Gravelines to Oldenburg | 298.28 mi (480.04 km) |
| Gravelines to Oldenburg in Holstein | 432.17 mi (695.51 km) |
| Gravelines to Olfen | 232.29 mi (373.83 km) |
| Gravelines to Olpe | 248.04 mi (399.18 km) |
| Gravelines to Olsberg | 276.41 mi (444.85 km) |
| Gravelines to Oranienburg | 488.88 mi (786.77 km) |
| Gravelines to Ortenberg | 306.36 mi (493.04 km) |
| Gravelines to Oschatz | 475.99 mi (766.03 km) |
