| Gronau to Obernburg am Main | 187.59 mi (301.90 km) |
| Gronau to Obernkirchen | 87.92 mi (141.49 km) |
| Gronau to Oberschleissheim | 338.91 mi (545.42 km) |
| Gronau to Oberstdorf | 361.79 mi (582.24 km) |
| Gronau to Obertraubling | 317.45 mi (510.88 km) |
| Gronau to Obertshausen | 167.36 mi (269.34 km) |
| Gronau to Oberursel | 153.90 mi (247.68 km) |
| Gronau to Ochsenfurt | 220.64 mi (355.08 km) |
| Gronau to Ochsenhausen | 313.62 mi (504.72 km) |
| Gronau to Ochtrup | 6.31 mi (10.15 km) |
| Gronau to Odenthal | 81.54 mi (131.22 km) |
| Gronau to Oelde | 53.91 mi (86.77 km) |
| Gronau to Oelsnitz | 253.65 mi (408.21 km) |
| Gronau to Oer-Erkenschwick | 40.40 mi (65.02 km) |
| Gronau to Oerlinghausen | 71.04 mi (114.33 km) |
