| Glen Carbon to Octeville | 4,183.99 mi (6,733.48 km) |
| Glen Carbon to Oignies | 4,339.13 mi (6,983.16 km) |
| Glen Carbon to Oissel | 4,302.04 mi (6,923.46 km) |
| Glen Carbon to Olivet | 4,383.66 mi (7,054.83 km) |
| Glen Carbon to Ollioules | 4,716.82 mi (7,590.98 km) |
| Glen Carbon to Olonne-sur-Mer | 4,276.30 mi (6,882.04 km) |
| Glen Carbon to Oloron-Sainte-Marie | 4,438.13 mi (7,142.48 km) |
| Glen Carbon to Onet Village | 4,534.32 mi (7,297.29 km) |
| Glen Carbon to Onnaing | 4,365.12 mi (7,024.98 km) |
| Glen Carbon to Orange | 4,635.77 mi (7,460.55 km) |
| Glen Carbon to Orchies | 4,348.59 mi (6,998.38 km) |
| Glen Carbon to Orleans | 4,382.69 mi (7,053.27 km) |
| Glen Carbon to Orly | 4,373.59 mi (7,038.61 km) |
| Glen Carbon to Ormesson-sur-Marne | 4,377.95 mi (7,045.63 km) |
| Glen Carbon to Orsay | 4,366.97 mi (7,027.96 km) |
