| Montegrotto Terme to Octeville | 692.30 mi (1,114.14 km) |
| Montegrotto Terme to Oignies | 539.44 mi (868.14 km) |
| Montegrotto Terme to Oissel | 571.38 mi (919.56 km) |
| Montegrotto Terme to Olivet | 500.25 mi (805.08 km) |
| Montegrotto Terme to Ollioules | 330.54 mi (531.96 km) |
| Montegrotto Terme to Olonne-sur-Mer | 655.86 mi (1,055.50 km) |
| Montegrotto Terme to Oloron-Sainte-Marie | 629.92 mi (1,013.76 km) |
| Montegrotto Terme to Onet Village | 454.83 mi (731.98 km) |
| Montegrotto Terme to Onnaing | 515.14 mi (829.04 km) |
| Montegrotto Terme to Orange | 351.96 mi (566.43 km) |
| Montegrotto Terme to Orchies | 531.01 mi (854.59 km) |
| Montegrotto Terme to Orleans | 500.66 mi (805.73 km) |
| Montegrotto Terme to Orly | 500.56 mi (805.57 km) |
| Montegrotto Terme to Ormesson-sur-Marne | 495.77 mi (797.86 km) |
| Montegrotto Terme to Orsay | 507.81 mi (817.24 km) |
