| Targu Ocna to Oberkirch | 878.40 mi (1,413.65 km) |
| Targu Ocna to Obernburg am Main | 841.54 mi (1,354.32 km) |
| Targu Ocna to Obernkirchen | 887.67 mi (1,428.57 km) |
| Targu Ocna to Oberschleissheim | 717.58 mi (1,154.83 km) |
| Targu Ocna to Oberstdorf | 774.73 mi (1,246.80 km) |
| Targu Ocna to Obertraubling | 696.97 mi (1,121.67 km) |
| Targu Ocna to Obertshausen | 857.88 mi (1,380.63 km) |
| Targu Ocna to Oberursel | 870.84 mi (1,401.48 km) |
| Targu Ocna to Ochsenfurt | 798.53 mi (1,285.11 km) |
| Targu Ocna to Ochsenhausen | 791.13 mi (1,273.20 km) |
| Targu Ocna to Ochtrup | 963.37 mi (1,550.39 km) |
| Targu Ocna to Odenthal | 945.35 mi (1,521.40 km) |
| Targu Ocna to Oelde | 916.73 mi (1,475.34 km) |
| Targu Ocna to Oelsnitz | 721.08 mi (1,160.46 km) |
| Targu Ocna to Oer-Erkenschwick | 949.92 mi (1,528.75 km) |
