| Giessen to Obernburg am Main | 55.48 mi (89.29 km) |
| Giessen to Obernkirchen | 117.90 mi (189.75 km) |
| Giessen to Oberschleissheim | 207.29 mi (333.60 km) |
| Giessen to Oberstdorf | 231.12 mi (371.96 km) |
| Giessen to Obertraubling | 192.01 mi (309.02 km) |
| Giessen to Obertshausen | 36.44 mi (58.65 km) |
| Giessen to Oberursel | 26.55 mi (42.73 km) |
| Giessen to Ochsenfurt | 89.47 mi (143.99 km) |
| Giessen to Ochsenhausen | 182.84 mi (294.25 km) |
| Giessen to Ochtrup | 128.89 mi (207.44 km) |
| Giessen to Odenthal | 74.47 mi (119.85 km) |
| Giessen to Oelde | 89.22 mi (143.58 km) |
| Giessen to Oelsnitz | 154.24 mi (248.22 km) |
| Giessen to Oer-Erkenschwick | 95.52 mi (153.72 km) |
| Giessen to Oerlinghausen | 95.58 mi (153.83 km) |
