| Western Springs to Oberkirch | 4,379.35 mi (7,047.88 km) |
| Western Springs to Obernburg am Main | 4,368.47 mi (7,030.37 km) |
| Western Springs to Obernkirchen | 4,275.05 mi (6,880.04 km) |
| Western Springs to Oberschleissheim | 4,521.46 mi (7,276.59 km) |
| Western Springs to Oberstdorf | 4,507.06 mi (7,253.41 km) |
| Western Springs to Obertraubling | 4,514.48 mi (7,265.36 km) |
| Western Springs to Obertshausen | 4,348.36 mi (6,998.01 km) |
| Western Springs to Oberursel | 4,333.68 mi (6,974.38 km) |
| Western Springs to Ochsenfurt | 4,409.98 mi (7,097.18 km) |
| Western Springs to Ochsenhausen | 4,467.99 mi (7,190.53 km) |
| Western Springs to Ochtrup | 4,208.44 mi (6,772.83 km) |
| Western Springs to Odenthal | 4,248.78 mi (6,837.74 km) |
| Western Springs to Oelde | 4,256.68 mi (6,850.46 km) |
| Western Springs to Oelsnitz | 4,455.75 mi (7,170.83 km) |
| Western Springs to Oer-Erkenschwick | 4,231.24 mi (6,809.52 km) |
