| Horndean to Oberkirch | 437.26 mi (703.70 km) |
| Horndean to Obernburg am Main | 452.43 mi (728.12 km) |
| Horndean to Obernkirchen | 443.71 mi (714.08 km) |
| Horndean to Oberschleissheim | 591.24 mi (951.51 km) |
| Horndean to Oberstdorf | 563.25 mi (906.47 km) |
| Horndean to Obertraubling | 599.72 mi (965.16 km) |
| Horndean to Obertshausen | 435.69 mi (701.18 km) |
| Horndean to Oberursel | 422.75 mi (680.35 km) |
| Horndean to Ochsenfurt | 495.69 mi (797.73 km) |
| Horndean to Ochsenhausen | 528.31 mi (850.23 km) |
| Horndean to Ochtrup | 362.58 mi (583.52 km) |
| Horndean to Odenthal | 352.88 mi (567.90 km) |
| Horndean to Oelde | 399.29 mi (642.59 km) |
| Horndean to Oelsnitz | 576.72 mi (928.14 km) |
| Horndean to Oer-Erkenschwick | 359.78 mi (579.00 km) |
