| Delaware to Opole | 4,555.54 mi (7,331.44 km) |
| Delaware to Orzesze | 4,605.52 mi (7,411.86 km) |
| Delaware to Osowa | 4,427.53 mi (7,125.42 km) |
| Delaware to Ostroda | 4,505.97 mi (7,251.66 km) |
| Delaware to Ostroleka | 4,585.05 mi (7,378.92 km) |
| Delaware to Ostrow Mazowiecka | 4,607.16 mi (7,414.51 km) |
| Delaware to Ostrow Wielkopolski | 4,512.74 mi (7,262.55 km) |
| Delaware to Ostrowiec Swietokrzyski | 4,667.33 mi (7,511.33 km) |
| Delaware to Ostrzeszow | 4,525.99 mi (7,283.88 km) |
| Delaware to Oswiecim | 4,626.99 mi (7,446.42 km) |
| Delaware to Otwock | 4,613.86 mi (7,425.29 km) |
| Delaware to Ozarow Mazowiecki | 4,593.83 mi (7,393.05 km) |
| Delaware to Ozimek | 4,565.33 mi (7,347.19 km) |
| Delaware to Ozorkow | 4,551.62 mi (7,325.13 km) |
| Delaware to Pabianice | 4,567.77 mi (7,351.11 km) |
