| Ionia to Oberkirch | 4,217.63 mi (6,787.62 km) |
| Ionia to Obernburg am Main | 4,207.85 mi (6,771.88 km) |
| Ionia to Obernkirchen | 4,116.18 mi (6,624.36 km) |
| Ionia to Oberschleissheim | 4,360.53 mi (7,017.60 km) |
| Ionia to Oberstdorf | 4,345.28 mi (6,993.05 km) |
| Ionia to Obertraubling | 4,354.19 mi (7,007.39 km) |
| Ionia to Obertshausen | 4,187.81 mi (6,739.62 km) |
| Ionia to Oberursel | 4,173.14 mi (6,716.03 km) |
| Ionia to Ochsenfurt | 4,249.51 mi (6,838.92 km) |
| Ionia to Ochsenhausen | 4,306.50 mi (6,930.64 km) |
| Ionia to Ochtrup | 4,048.95 mi (6,516.15 km) |
| Ionia to Odenthal | 4,088.40 mi (6,579.65 km) |
| Ionia to Oelde | 4,097.18 mi (6,593.78 km) |
| Ionia to Oelsnitz | 4,296.45 mi (6,914.46 km) |
| Ionia to Oer-Erkenschwick | 4,071.34 mi (6,552.19 km) |
