| Webster Groves to Octeville | 4,206.83 mi (6,770.23 km) |
| Webster Groves to Oignies | 4,361.76 mi (7,019.57 km) |
| Webster Groves to Oissel | 4,324.82 mi (6,960.13 km) |
| Webster Groves to Olivet | 4,406.54 mi (7,091.65 km) |
| Webster Groves to Ollioules | 4,739.89 mi (7,628.12 km) |
| Webster Groves to Olonne-sur-Mer | 4,299.36 mi (6,919.15 km) |
| Webster Groves to Oloron-Sainte-Marie | 4,461.33 mi (7,179.82 km) |
| Webster Groves to Onet Village | 4,557.41 mi (7,334.44 km) |
| Webster Groves to Onnaing | 4,387.73 mi (7,061.37 km) |
| Webster Groves to Orange | 4,658.82 mi (7,497.64 km) |
| Webster Groves to Orchies | 4,371.21 mi (7,034.78 km) |
| Webster Groves to Orleans | 4,405.57 mi (7,090.08 km) |
| Webster Groves to Orly | 4,396.38 mi (7,075.30 km) |
| Webster Groves to Ormesson-sur-Marne | 4,400.74 mi (7,082.30 km) |
| Webster Groves to Orsay | 4,389.78 mi (7,064.66 km) |
