| Mercogliano to Octeville | 994.61 mi (1,600.66 km) |
| Mercogliano to Oignies | 867.68 mi (1,396.39 km) |
| Mercogliano to Oissel | 881.40 mi (1,418.47 km) |
| Mercogliano to Olivet | 793.25 mi (1,276.61 km) |
| Mercogliano to Ollioules | 481.26 mi (774.51 km) |
| Mercogliano to Olonne-sur-Mer | 908.87 mi (1,462.69 km) |
| Mercogliano to Oloron-Sainte-Marie | 801.68 mi (1,290.18 km) |
| Mercogliano to Onet Village | 660.88 mi (1,063.59 km) |
| Mercogliano to Onnaing | 845.06 mi (1,360.00 km) |
| Mercogliano to Orange | 551.91 mi (888.22 km) |
| Mercogliano to Orchies | 860.20 mi (1,384.35 km) |
| Mercogliano to Orleans | 794.35 mi (1,278.39 km) |
| Mercogliano to Orly | 809.45 mi (1,302.68 km) |
| Mercogliano to Ormesson-sur-Marne | 805.96 mi (1,297.07 km) |
| Mercogliano to Orsay | 815.03 mi (1,311.67 km) |
