| Willow Grove to Oberkirch | 3,945.75 mi (6,350.07 km) |
| Willow Grove to Obernburg am Main | 3,950.47 mi (6,357.66 km) |
| Willow Grove to Obernkirchen | 3,880.17 mi (6,244.53 km) |
| Willow Grove to Oberschleissheim | 4,097.61 mi (6,594.47 km) |
| Willow Grove to Oberstdorf | 4,071.18 mi (6,551.94 km) |
| Willow Grove to Obertraubling | 4,099.17 mi (6,596.97 km) |
| Willow Grove to Obertshausen | 3,931.43 mi (6,327.03 km) |
| Willow Grove to Oberursel | 3,917.17 mi (6,304.08 km) |
| Willow Grove to Ochsenfurt | 3,993.41 mi (6,426.77 km) |
| Willow Grove to Ochsenhausen | 4,036.75 mi (6,496.52 km) |
| Willow Grove to Ochtrup | 3,806.81 mi (6,126.47 km) |
| Willow Grove to Odenthal | 3,835.40 mi (6,172.48 km) |
| Willow Grove to Oelde | 3,854.42 mi (6,203.09 km) |
| Willow Grove to Oelsnitz | 4,053.61 mi (6,523.65 km) |
| Willow Grove to Oer-Erkenschwick | 3,824.23 mi (6,154.51 km) |
