| Houghton Regis to Opole | 800.03 mi (1,287.52 km) |
| Houghton Regis to Orzesze | 843.78 mi (1,357.93 km) |
| Houghton Regis to Osowa | 803.26 mi (1,292.72 km) |
| Houghton Regis to Ostroda | 861.82 mi (1,386.97 km) |
| Houghton Regis to Ostroleka | 929.25 mi (1,495.48 km) |
| Houghton Regis to Ostrow Mazowiecka | 944.56 mi (1,520.11 km) |
| Houghton Regis to Ostrow Wielkopolski | 782.20 mi (1,258.83 km) |
| Houghton Regis to Ostrowiec Swietokrzyski | 943.48 mi (1,518.39 km) |
| Houghton Regis to Ostrzeszow | 789.71 mi (1,270.91 km) |
| Houghton Regis to Oswiecim | 866.00 mi (1,393.68 km) |
| Houghton Regis to Otwock | 923.38 mi (1,486.04 km) |
| Houghton Regis to Ozarow Mazowiecki | 902.88 mi (1,453.04 km) |
| Houghton Regis to Ozimek | 811.85 mi (1,306.55 km) |
| Houghton Regis to Ozorkow | 841.21 mi (1,353.79 km) |
| Houghton Regis to Pabianice | 848.59 mi (1,365.67 km) |
