| Allentown to Oberkirch | 3,941.25 mi (6,342.82 km) |
| Allentown to Obernburg am Main | 3,944.86 mi (6,348.64 km) |
| Allentown to Obernkirchen | 3,872.92 mi (6,232.87 km) |
| Allentown to Oberschleissheim | 4,092.52 mi (6,586.28 km) |
| Allentown to Oberstdorf | 4,066.94 mi (6,545.10 km) |
| Allentown to Obertraubling | 4,093.48 mi (6,587.82 km) |
| Allentown to Obertshausen | 3,925.73 mi (6,317.86 km) |
| Allentown to Oberursel | 3,911.43 mi (6,294.84 km) |
| Allentown to Ochsenfurt | 3,987.73 mi (6,417.63 km) |
| Allentown to Ochsenhausen | 4,032.14 mi (6,489.11 km) |
| Allentown to Ochtrup | 3,799.96 mi (6,115.44 km) |
| Allentown to Odenthal | 3,829.38 mi (6,162.79 km) |
| Allentown to Oelde | 3,847.65 mi (6,192.19 km) |
| Allentown to Oelsnitz | 4,046.99 mi (6,512.99 km) |
| Allentown to Oer-Erkenschwick | 3,817.76 mi (6,144.09 km) |
