| Mercer Island to Opole | 5,248.90 mi (8,447.28 km) |
| Mercer Island to Orzesze | 5,296.80 mi (8,524.37 km) |
| Mercer Island to Osowa | 5,026.47 mi (8,089.32 km) |
| Mercer Island to Ostroda | 5,098.25 mi (8,204.83 km) |
| Mercer Island to Ostroleka | 5,165.73 mi (8,313.44 km) |
| Mercer Island to Ostrow Mazowiecka | 5,188.24 mi (8,349.66 km) |
| Mercer Island to Ostrow Wielkopolski | 5,185.89 mi (8,345.89 km) |
| Mercer Island to Ostrowiec Swietokrzyski | 5,297.12 mi (8,524.89 km) |
| Mercer Island to Ostrzeszow | 5,202.52 mi (8,372.65 km) |
| Mercer Island to Oswiecim | 5,312.83 mi (8,550.18 km) |
| Mercer Island to Otwock | 5,220.28 mi (8,401.23 km) |
| Mercer Island to Ozarow Mazowiecki | 5,205.75 mi (8,377.85 km) |
| Mercer Island to Ozimek | 5,253.94 mi (8,455.40 km) |
| Mercer Island to Ozorkow | 5,193.89 mi (8,358.75 km) |
| Mercer Island to Pabianice | 5,215.46 mi (8,393.47 km) |
