| Monterotondo to Octeville | 860.87 mi (1,385.44 km) |
| Monterotondo to Oignies | 740.15 mi (1,191.16 km) |
| Monterotondo to Oissel | 748.95 mi (1,205.32 km) |
| Monterotondo to Olivet | 659.20 mi (1,060.87 km) |
| Monterotondo to Ollioules | 352.36 mi (567.07 km) |
| Monterotondo to Olonne-sur-Mer | 774.73 mi (1,246.81 km) |
| Monterotondo to Oloron-Sainte-Marie | 676.21 mi (1,088.25 km) |
| Monterotondo to Onet Village | 529.11 mi (851.52 km) |
| Monterotondo to Onnaing | 718.44 mi (1,156.22 km) |
| Monterotondo to Orange | 419.28 mi (674.77 km) |
| Monterotondo to Orchies | 733.14 mi (1,179.87 km) |
| Monterotondo to Orleans | 660.35 mi (1,062.73 km) |
| Monterotondo to Orly | 677.11 mi (1,089.71 km) |
| Monterotondo to Ormesson-sur-Marne | 673.85 mi (1,084.45 km) |
| Monterotondo to Orsay | 682.42 mi (1,098.25 km) |
