| Calais to Oignies | 59.75 mi (96.16 km) |
| Calais to Oissel | 116.03 mi (186.73 km) |
| Calais to Olivet | 213.11 mi (342.96 km) |
| Calais to Ollioules | 571.09 mi (919.08 km) |
| Calais to Olonne-sur-Mer | 346.70 mi (557.96 km) |
| Calais to Oloron-Sainte-Marie | 548.05 mi (882.01 km) |
| Calais to Onet Village | 456.09 mi (734.01 km) |
| Calais to Onnaing | 85.53 mi (137.65 km) |
| Calais to Orange | 490.15 mi (788.82 km) |
| Calais to Orchies | 68.97 mi (110.99 km) |
| Calais to Orleans | 210.44 mi (338.68 km) |
| Calais to Orly | 154.16 mi (248.09 km) |
| Calais to Ormesson-sur-Marne | 152.45 mi (245.35 km) |
| Calais to Orsay | 156.16 mi (251.31 km) |
| Calais to Orthez | 529.88 mi (852.77 km) |
