| Ardahan to Oerlinghausen | 1,761.91 mi (2,835.52 km) |
| Ardahan to Oestrich-Winkel | 1,768.69 mi (2,846.43 km) |
| Ardahan to Offenburg | 1,761.96 mi (2,835.59 km) |
| Ardahan to Oftersheim | 1,737.79 mi (2,796.70 km) |
| Ardahan to Ohrdruf | 1,658.94 mi (2,669.81 km) |
| Ardahan to Ohringen | 1,695.49 mi (2,728.63 km) |
| Ardahan to Olbernhau | 1,545.57 mi (2,487.35 km) |
| Ardahan to Olching | 1,605.56 mi (2,583.90 km) |
| Ardahan to Oldenburg | 1,798.17 mi (2,893.88 km) |
| Ardahan to Oldenburg in Holstein | 1,715.66 mi (2,761.08 km) |
| Ardahan to Olfen | 1,812.53 mi (2,916.99 km) |
| Ardahan to Olpe | 1,785.55 mi (2,873.57 km) |
| Ardahan to Olsberg | 1,761.58 mi (2,834.99 km) |
| Ardahan to Oranienburg | 1,589.80 mi (2,558.53 km) |
| Ardahan to Ortenberg | 1,725.74 mi (2,777.31 km) |
