| Naperville to Oerlinghausen | 4,282.42 mi (6,891.89 km) |
| Naperville to Oestrich-Winkel | 4,332.53 mi (6,972.53 km) |
| Naperville to Offenburg | 4,388.84 mi (7,063.15 km) |
| Naperville to Oftersheim | 4,378.41 mi (7,046.36 km) |
| Naperville to Ohrdruf | 4,400.19 mi (7,081.43 km) |
| Naperville to Ohringen | 4,419.12 mi (7,111.89 km) |
| Naperville to Olbernhau | 4,499.23 mi (7,240.81 km) |
| Naperville to Olching | 4,526.66 mi (7,284.95 km) |
| Naperville to Oldenburg | 4,222.63 mi (6,795.67 km) |
| Naperville to Oldenburg in Holstein | 4,271.30 mi (6,873.99 km) |
| Naperville to Olfen | 4,245.58 mi (6,832.61 km) |
| Naperville to Olpe | 4,287.98 mi (6,900.84 km) |
| Naperville to Olsberg | 4,299.06 mi (6,918.66 km) |
| Naperville to Oranienburg | 4,411.36 mi (7,099.40 km) |
| Naperville to Ortenberg | 4,357.77 mi (7,013.16 km) |
