| Potomac to Opole | 4,402.02 mi (7,084.37 km) |
| Potomac to Orzesze | 4,451.17 mi (7,163.46 km) |
| Potomac to Osowa | 4,293.02 mi (6,908.94 km) |
| Potomac to Ostroda | 4,370.59 mi (7,033.78 km) |
| Potomac to Ostroleka | 4,449.64 mi (7,161.00 km) |
| Potomac to Ostrow Mazowiecka | 4,471.14 mi (7,195.61 km) |
| Potomac to Ostrow Wielkopolski | 4,363.61 mi (7,022.55 km) |
| Potomac to Ostrowiec Swietokrzyski | 4,521.73 mi (7,277.02 km) |
| Potomac to Ostrzeszow | 4,375.98 mi (7,042.46 km) |
| Potomac to Oswiecim | 4,473.05 mi (7,198.67 km) |
| Potomac to Otwock | 4,473.44 mi (7,199.30 km) |
| Potomac to Ozarow Mazowiecki | 4,452.98 mi (7,166.37 km) |
| Potomac to Ozimek | 4,412.37 mi (7,101.02 km) |
| Potomac to Ozorkow | 4,406.72 mi (7,091.93 km) |
| Potomac to Pabianice | 4,421.57 mi (7,115.83 km) |
