| Clausthal-Zellerfeld to Obernburg am Main | 145.43 mi (234.04 km) |
| Clausthal-Zellerfeld to Obernkirchen | 60.79 mi (97.83 km) |
| Clausthal-Zellerfeld to Oberschleissheim | 251.62 mi (404.95 km) |
| Clausthal-Zellerfeld to Oberstdorf | 303.70 mi (488.75 km) |
| Clausthal-Zellerfeld to Obertraubling | 212.09 mi (341.33 km) |
| Clausthal-Zellerfeld to Obertshausen | 136.76 mi (220.09 km) |
| Clausthal-Zellerfeld to Oberursel | 134.50 mi (216.46 km) |
| Clausthal-Zellerfeld to Ochsenfurt | 149.36 mi (240.37 km) |
| Clausthal-Zellerfeld to Ochsenhausen | 258.49 mi (415.99 km) |
| Clausthal-Zellerfeld to Ochtrup | 136.60 mi (219.84 km) |
| Clausthal-Zellerfeld to Odenthal | 148.58 mi (239.11 km) |
| Clausthal-Zellerfeld to Oelde | 93.36 mi (150.25 km) |
| Clausthal-Zellerfeld to Oelsnitz | 124.53 mi (200.41 km) |
| Clausthal-Zellerfeld to Oer-Erkenschwick | 132.50 mi (213.24 km) |
| Clausthal-Zellerfeld to Oerlinghausen | 72.04 mi (115.94 km) |
