| Middle River to Opole | 4,356.81 mi (7,011.61 km) |
| Middle River to Orzesze | 4,405.91 mi (7,090.63 km) |
| Middle River to Osowa | 4,248.79 mi (6,837.77 km) |
| Middle River to Ostroda | 4,326.30 mi (6,962.50 km) |
| Middle River to Ostroleka | 4,405.33 mi (7,089.70 km) |
| Middle River to Ostrow Mazowiecka | 4,426.80 mi (7,124.25 km) |
| Middle River to Ostrow Wielkopolski | 4,318.61 mi (6,950.13 km) |
| Middle River to Ostrowiec Swietokrzyski | 4,476.88 mi (7,204.84 km) |
| Middle River to Ostrzeszow | 4,330.94 mi (6,969.98 km) |
| Middle River to Oswiecim | 4,427.80 mi (7,125.86 km) |
| Middle River to Otwock | 4,428.86 mi (7,127.56 km) |
| Middle River to Ozarow Mazowiecki | 4,408.38 mi (7,094.60 km) |
| Middle River to Ozimek | 4,367.18 mi (7,028.30 km) |
| Middle River to Ozorkow | 4,361.93 mi (7,019.84 km) |
| Middle River to Pabianice | 4,376.71 mi (7,043.63 km) |
