| Rockford to Opole | 4,662.35 mi (7,503.32 km) |
| Rockford to Orzesze | 4,712.87 mi (7,584.62 km) |
| Rockford to Osowa | 4,514.39 mi (7,265.21 km) |
| Rockford to Ostroda | 4,593.15 mi (7,391.96 km) |
| Rockford to Ostroleka | 4,671.64 mi (7,518.28 km) |
| Rockford to Ostrow Mazowiecka | 4,694.26 mi (7,554.68 km) |
| Rockford to Ostrow Wielkopolski | 4,615.00 mi (7,427.13 km) |
| Rockford to Ostrowiec Swietokrzyski | 4,764.52 mi (7,667.75 km) |
| Rockford to Ostrzeszow | 4,629.13 mi (7,449.87 km) |
| Rockford to Oswiecim | 4,733.74 mi (7,618.21 km) |
| Rockford to Otwock | 4,705.74 mi (7,573.16 km) |
| Rockford to Ozarow Mazowiecki | 4,686.34 mi (7,541.94 km) |
| Rockford to Ozimek | 4,671.44 mi (7,517.95 km) |
| Rockford to Ozorkow | 4,648.92 mi (7,481.71 km) |
| Rockford to Pabianice | 4,666.37 mi (7,509.80 km) |
