| Casper to Oberkirch | 4,975.09 mi (8,006.63 km) |
| Casper to Obernburg am Main | 4,944.06 mi (7,956.69 km) |
| Casper to Obernkirchen | 4,823.88 mi (7,763.28 km) |
| Casper to Oberschleissheim | 5,099.33 mi (8,206.57 km) |
| Casper to Oberstdorf | 5,101.43 mi (8,209.95 km) |
| Casper to Obertraubling | 5,081.23 mi (8,177.45 km) |
| Casper to Obertshausen | 4,923.28 mi (7,923.26 km) |
| Casper to Oberursel | 4,908.59 mi (7,899.61 km) |
| Casper to Ochsenfurt | 4,982.18 mi (8,018.05 km) |
| Casper to Ochsenhausen | 5,057.53 mi (8,139.31 km) |
| Casper to Ochtrup | 4,768.69 mi (7,674.46 km) |
| Casper to Odenthal | 4,822.76 mi (7,761.48 km) |
| Casper to Oelde | 4,815.86 mi (7,750.38 km) |
| Casper to Oelsnitz | 5,007.16 mi (8,058.24 km) |
| Casper to Oer-Erkenschwick | 4,797.60 mi (7,720.99 km) |
