| Horta to Oberkirch | 1,942.26 mi (3,125.76 km) |
| Horta to Obernburg am Main | 2,001.71 mi (3,221.45 km) |
| Horta to Obernkirchen | 2,031.42 mi (3,269.26 km) |
| Horta to Oberschleissheim | 2,099.61 mi (3,378.99 km) |
| Horta to Oberstdorf | 2,036.64 mi (3,277.66 km) |
| Horta to Obertraubling | 2,130.30 mi (3,428.38 km) |
| Horta to Obertshausen | 1,990.56 mi (3,203.49 km) |
| Horta to Oberursel | 1,980.89 mi (3,187.93 km) |
| Horta to Ochsenfurt | 2,040.86 mi (3,284.45 km) |
| Horta to Ochsenhausen | 2,024.33 mi (3,257.85 km) |
| Horta to Ochtrup | 1,951.18 mi (3,140.12 km) |
| Horta to Odenthal | 1,929.07 mi (3,104.54 km) |
| Horta to Oelde | 1,984.69 mi (3,194.05 km) |
| Horta to Oelsnitz | 2,139.77 mi (3,443.62 km) |
| Horta to Oer-Erkenschwick | 1,944.21 mi (3,128.91 km) |
