| Hillsborough to Oerlinghausen | 3,836.09 mi (6,173.59 km) |
| Hillsborough to Oestrich-Winkel | 3,864.99 mi (6,220.10 km) |
| Hillsborough to Offenburg | 3,906.88 mi (6,287.51 km) |
| Hillsborough to Oftersheim | 3,906.97 mi (6,287.65 km) |
| Hillsborough to Ohrdruf | 3,949.82 mi (6,356.63 km) |
| Hillsborough to Ohringen | 3,949.27 mi (6,355.74 km) |
| Hillsborough to Olbernhau | 4,056.60 mi (6,528.47 km) |
| Hillsborough to Olching | 4,054.28 mi (6,524.74 km) |
| Hillsborough to Oldenburg | 3,786.66 mi (6,094.04 km) |
| Hillsborough to Oldenburg in Holstein | 3,855.73 mi (6,205.19 km) |
| Hillsborough to Olfen | 3,792.62 mi (6,103.63 km) |
| Hillsborough to Olpe | 3,829.62 mi (6,163.18 km) |
| Hillsborough to Olsberg | 3,846.08 mi (6,189.66 km) |
| Hillsborough to Oranienburg | 3,988.27 mi (6,418.50 km) |
| Hillsborough to Ortenberg | 3,897.17 mi (6,271.88 km) |
