| Constanta to Opole | 671.07 mi (1,079.98 km) |
| Constanta to Orzesze | 620.76 mi (999.02 km) |
| Constanta to Osowa | 842.09 mi (1,355.21 km) |
| Constanta to Ostroda | 765.95 mi (1,232.67 km) |
| Constanta to Ostroleka | 693.71 mi (1,116.42 km) |
| Constanta to Ostrow Mazowiecka | 670.80 mi (1,079.55 km) |
| Constanta to Ostrow Wielkopolski | 718.47 mi (1,156.26 km) |
| Constanta to Ostrowiec Swietokrzyski | 575.91 mi (926.84 km) |
| Constanta to Ostrzeszow | 704.06 mi (1,133.07 km) |
| Constanta to Oswiecim | 599.59 mi (964.95 km) |
| Constanta to Otwock | 645.07 mi (1,038.13 km) |
| Constanta to Ozarow Mazowiecki | 662.12 mi (1,065.59 km) |
| Constanta to Ozimek | 661.73 mi (1,064.95 km) |
| Constanta to Ozorkow | 689.37 mi (1,109.44 km) |
| Constanta to Pabianice | 670.40 mi (1,078.90 km) |
