| Gross-Gerau to Obernburg am Main | 29.73 mi (47.85 km) |
| Gross-Gerau to Obernkirchen | 164.48 mi (264.71 km) |
| Gross-Gerau to Oberschleissheim | 180.94 mi (291.19 km) |
| Gross-Gerau to Oberstdorf | 191.73 mi (308.57 km) |
| Gross-Gerau to Obertraubling | 178.02 mi (286.50 km) |
| Gross-Gerau to Obertshausen | 18.53 mi (29.81 km) |
| Gross-Gerau to Oberursel | 20.05 mi (32.26 km) |
| Gross-Gerau to Ochsenfurt | 72.97 mi (117.43 km) |
| Gross-Gerau to Ochsenhausen | 143.82 mi (231.45 km) |
| Gross-Gerau to Ochtrup | 167.67 mi (269.84 km) |
| Gross-Gerau to Odenthal | 97.70 mi (157.23 km) |
| Gross-Gerau to Oelde | 133.06 mi (214.13 km) |
| Gross-Gerau to Oelsnitz | 166.51 mi (267.97 km) |
| Gross-Gerau to Oer-Erkenschwick | 130.68 mi (210.32 km) |
| Gross-Gerau to Oerlinghausen | 141.69 mi (228.03 km) |
