| Castleton to Octeville | 274.81 mi (442.27 km) |
| Castleton to Oignies | 307.69 mi (495.18 km) |
| Castleton to Oissel | 325.39 mi (523.66 km) |
| Castleton to Olivet | 433.78 mi (698.10 km) |
| Castleton to Ollioules | 809.37 mi (1,302.55 km) |
| Castleton to Olonne-sur-Mer | 487.75 mi (784.95 km) |
| Castleton to Oloron-Sainte-Marie | 721.87 mi (1,161.74 km) |
| Castleton to Onet Village | 672.67 mi (1,082.57 km) |
| Castleton to Onnaing | 330.39 mi (531.71 km) |
| Castleton to Orange | 725.32 mi (1,167.29 km) |
| Castleton to Orchies | 315.10 mi (507.10 km) |
| Castleton to Orleans | 431.47 mi (694.39 km) |
| Castleton to Orly | 388.77 mi (625.67 km) |
| Castleton to Ormesson-sur-Marne | 389.49 mi (626.82 km) |
| Castleton to Orsay | 387.14 mi (623.05 km) |
