| Tucson Mountains to Octeville | 5,321.28 mi (8,563.78 km) |
| Tucson Mountains to Oignies | 5,451.72 mi (8,773.70 km) |
| Tucson Mountains to Oissel | 5,432.11 mi (8,742.13 km) |
| Tucson Mountains to Olivet | 5,523.49 mi (8,889.19 km) |
| Tucson Mountains to Ollioules | 5,878.09 mi (9,459.87 km) |
| Tucson Mountains to Olonne-sur-Mer | 5,439.90 mi (8,754.67 km) |
| Tucson Mountains to Oloron-Sainte-Marie | 5,622.27 mi (9,048.17 km) |
| Tucson Mountains to Onet Village | 5,699.10 mi (9,171.81 km) |
| Tucson Mountains to Onnaing | 5,476.08 mi (8,812.90 km) |
| Tucson Mountains to Orange | 5,793.84 mi (9,324.29 km) |
| Tucson Mountains to Orchies | 5,460.15 mi (8,787.25 km) |
| Tucson Mountains to Orleans | 5,522.16 mi (8,887.06 km) |
| Tucson Mountains to Orly | 5,504.02 mi (8,857.86 km) |
| Tucson Mountains to Ormesson-sur-Marne | 5,507.45 mi (8,863.39 km) |
| Tucson Mountains to Orsay | 5,498.58 mi (8,849.11 km) |
