| Ionia to Orbetello | 4,585.36 mi (7,379.42 km) |
| Ionia to Oria | 4,927.37 mi (7,929.83 km) |
| Ionia to Oristano | 4,582.97 mi (7,375.57 km) |
| Ionia to Orta Nova | 4,813.80 mi (7,747.07 km) |
| Ionia to Orte | 4,631.79 mi (7,454.15 km) |
| Ionia to Ortona | 4,716.92 mi (7,591.16 km) |
| Ionia to Orvieto | 4,609.77 mi (7,418.71 km) |
| Ionia to Orzinuovi | 4,412.29 mi (7,100.90 km) |
| Ionia to Osimo | 4,631.81 mi (7,454.18 km) |
| Ionia to Ospitaletto | 4,411.53 mi (7,099.67 km) |
| Ionia to Ostuni | 4,914.80 mi (7,909.61 km) |
| Ionia to Ottaviano | 4,785.63 mi (7,701.73 km) |
| Ionia to Ovada | 4,391.71 mi (7,067.78 km) |
| Ionia to Ozieri | 4,571.97 mi (7,357.88 km) |
| Ionia to Paceco | 4,832.18 mi (7,776.65 km) |
