| Montemor-o-Velho to Octeville | 738.12 mi (1,187.89 km) |
| Montemor-o-Velho to Oignies | 908.00 mi (1,461.28 km) |
| Montemor-o-Velho to Oissel | 793.52 mi (1,277.05 km) |
| Montemor-o-Velho to Olivet | 746.62 mi (1,201.57 km) |
| Montemor-o-Velho to Ollioules | 776.60 mi (1,249.82 km) |
| Montemor-o-Velho to Olonne-sur-Mer | 560.08 mi (901.37 km) |
| Montemor-o-Velho to Oloron-Sainte-Marie | 466.04 mi (750.03 km) |
| Montemor-o-Velho to Onet Village | 644.69 mi (1,037.53 km) |
| Montemor-o-Velho to Onnaing | 922.36 mi (1,484.39 km) |
| Montemor-o-Velho to Orange | 742.52 mi (1,194.97 km) |
| Montemor-o-Velho to Orchies | 915.82 mi (1,473.87 km) |
| Montemor-o-Velho to Orleans | 748.68 mi (1,204.89 km) |
| Montemor-o-Velho to Orly | 804.35 mi (1,294.48 km) |
| Montemor-o-Velho to Ormesson-sur-Marne | 811.16 mi (1,305.44 km) |
| Montemor-o-Velho to Orsay | 795.39 mi (1,280.05 km) |
