| Barreiro to Opole | 1,551.20 mi (2,496.42 km) |
| Barreiro to Orzesze | 1,572.20 mi (2,530.22 km) |
| Barreiro to Osowa | 1,683.36 mi (2,709.10 km) |
| Barreiro to Ostroda | 1,714.35 mi (2,758.98 km) |
| Barreiro to Ostroleka | 1,757.06 mi (2,827.72 km) |
| Barreiro to Ostrow Mazowiecka | 1,763.17 mi (2,837.55 km) |
| Barreiro to Ostrow Wielkopolski | 1,573.08 mi (2,531.63 km) |
| Barreiro to Ostrowiec Swietokrzyski | 1,699.79 mi (2,735.55 km) |
| Barreiro to Ostrzeszow | 1,571.18 mi (2,528.57 km) |
| Barreiro to Oswiecim | 1,589.40 mi (2,557.89 km) |
| Barreiro to Otwock | 1,721.43 mi (2,770.37 km) |
| Barreiro to Ozarow Mazowiecki | 1,705.44 mi (2,744.64 km) |
| Barreiro to Ozimek | 1,562.75 mi (2,515.00 km) |
| Barreiro to Ozorkow | 1,639.29 mi (2,638.18 km) |
| Barreiro to Pabianice | 1,634.88 mi (2,631.08 km) |
