| Idanha-a-Nova to Octeville | 724.27 mi (1,165.60 km) |
| Idanha-a-Nova to Oignies | 881.13 mi (1,418.05 km) |
| Idanha-a-Nova to Oissel | 768.12 mi (1,236.17 km) |
| Idanha-a-Nova to Olivet | 711.97 mi (1,145.80 km) |
| Idanha-a-Nova to Ollioules | 711.38 mi (1,144.85 km) |
| Idanha-a-Nova to Olonne-sur-Mer | 533.31 mi (858.27 km) |
| Idanha-a-Nova to Oloron-Sainte-Marie | 410.49 mi (660.62 km) |
| Idanha-a-Nova to Onet Village | 589.27 mi (948.33 km) |
| Idanha-a-Nova to Onnaing | 893.55 mi (1,438.02 km) |
| Idanha-a-Nova to Orange | 682.57 mi (1,098.49 km) |
| Idanha-a-Nova to Orchies | 888.28 mi (1,429.55 km) |
| Idanha-a-Nova to Orleans | 714.19 mi (1,149.37 km) |
| Idanha-a-Nova to Orly | 772.23 mi (1,242.78 km) |
| Idanha-a-Nova to Ormesson-sur-Marne | 778.79 mi (1,253.34 km) |
| Idanha-a-Nova to Orsay | 763.68 mi (1,229.03 km) |
