| Rock Island to Oerlinghausen | 4,382.10 mi (7,052.31 km) |
| Rock Island to Oestrich-Winkel | 4,434.98 mi (7,137.41 km) |
| Rock Island to Offenburg | 4,493.11 mi (7,230.96 km) |
| Rock Island to Oftersheim | 4,481.30 mi (7,211.95 km) |
| Rock Island to Ohrdruf | 4,500.19 mi (7,242.36 km) |
| Rock Island to Ohringen | 4,521.73 mi (7,277.01 km) |
| Rock Island to Olbernhau | 4,597.97 mi (7,399.71 km) |
| Rock Island to Olching | 4,629.41 mi (7,450.32 km) |
| Rock Island to Oldenburg | 4,321.02 mi (6,954.01 km) |
| Rock Island to Oldenburg in Holstein | 4,366.76 mi (7,027.62 km) |
| Rock Island to Olfen | 4,346.24 mi (6,994.60 km) |
| Rock Island to Olpe | 4,389.29 mi (7,063.87 km) |
| Rock Island to Olsberg | 4,399.61 mi (7,080.49 km) |
| Rock Island to Oranienburg | 4,507.56 mi (7,254.22 km) |
| Rock Island to Ortenberg | 4,459.25 mi (7,176.46 km) |
