| Winnetka to Orbetello | 4,729.73 mi (7,611.76 km) |
| Winnetka to Oria | 5,070.65 mi (8,160.42 km) |
| Winnetka to Oristano | 4,729.21 mi (7,610.93 km) |
| Winnetka to Orta Nova | 4,957.31 mi (7,978.02 km) |
| Winnetka to Orte | 4,775.79 mi (7,685.89 km) |
| Winnetka to Ortona | 4,860.32 mi (7,821.93 km) |
| Winnetka to Orvieto | 4,753.71 mi (7,650.36 km) |
| Winnetka to Orzinuovi | 4,555.35 mi (7,331.14 km) |
| Winnetka to Osimo | 4,774.87 mi (7,684.41 km) |
| Winnetka to Ospitaletto | 4,554.45 mi (7,329.68 km) |
| Winnetka to Ostuni | 5,057.97 mi (8,140.02 km) |
| Winnetka to Ottaviano | 4,929.81 mi (7,933.76 km) |
| Winnetka to Ovada | 4,535.63 mi (7,299.40 km) |
| Winnetka to Ozieri | 4,717.84 mi (7,592.62 km) |
| Winnetka to Paceco | 4,978.22 mi (8,011.67 km) |
