| Isernia to Oberkirch | 564.86 mi (909.05 km) |
| Isernia to Obernburg am Main | 619.63 mi (997.20 km) |
| Isernia to Obernkirchen | 774.90 mi (1,247.08 km) |
| Isernia to Oberschleissheim | 477.45 mi (768.38 km) |
| Isernia to Oberstdorf | 446.01 mi (717.79 km) |
| Isernia to Obertraubling | 518.56 mi (834.55 km) |
| Isernia to Obertshausen | 639.67 mi (1,029.46 km) |
| Isernia to Oberursel | 653.17 mi (1,051.18 km) |
| Isernia to Ochsenfurt | 591.20 mi (951.44 km) |
| Isernia to Ochsenhausen | 493.78 mi (794.66 km) |
| Isernia to Ochtrup | 803.70 mi (1,293.44 km) |
| Isernia to Odenthal | 734.10 mi (1,181.42 km) |
| Isernia to Oelde | 762.79 mi (1,227.59 km) |
| Isernia to Oelsnitz | 616.99 mi (992.94 km) |
| Isernia to Oer-Erkenschwick | 768.01 mi (1,236.00 km) |
