| Castricum to Orzesze | 628.81 mi (1,011.97 km) |
| Castricum to Osowa | 581.08 mi (935.17 km) |
| Castricum to Ostroda | 638.04 mi (1,026.83 km) |
| Castricum to Ostroleka | 705.10 mi (1,134.75 km) |
| Castricum to Ostrow Mazowiecka | 720.45 mi (1,159.44 km) |
| Castricum to Ostrow Wielkopolski | 560.78 mi (902.49 km) |
| Castricum to Ostrowiec Swietokrzyski | 722.87 mi (1,163.35 km) |
| Castricum to Ostrzeszow | 569.12 mi (915.91 km) |
| Castricum to Oswiecim | 651.09 mi (1,047.82 km) |
| Castricum to Otwock | 699.95 mi (1,126.46 km) |
| Castricum to Ozarow Mazowiecki | 679.36 mi (1,093.32 km) |
| Castricum to Ozimek | 594.56 mi (956.85 km) |
| Castricum to Ozorkow | 618.42 mi (995.24 km) |
| Castricum to Pabianice | 626.60 mi (1,008.42 km) |
| Castricum to Parczew | 773.13 mi (1,244.23 km) |
