| Donaueschingen to Navodari | 991.81 mi (1,596.17 km) |
| Donaueschingen to Negresti-Oas | 689.96 mi (1,110.39 km) |
| Donaueschingen to Nehoiu | 861.10 mi (1,385.81 km) |
| Donaueschingen to Ocna Mures | 728.09 mi (1,171.75 km) |
| Donaueschingen to Odobesti | 887.69 mi (1,428.60 km) |
| Donaueschingen to Odorheiu Secuiesc | 796.04 mi (1,281.10 km) |
| Donaueschingen to Oltenita | 907.64 mi (1,460.71 km) |
| Donaueschingen to Onesti | 864.87 mi (1,391.88 km) |
| Donaueschingen to Oradea | 628.32 mi (1,011.19 km) |
| Donaueschingen to Orastie | 707.70 mi (1,138.93 km) |
| Donaueschingen to Oravita | 657.52 mi (1,058.17 km) |
| Donaueschingen to Orsova | 698.06 mi (1,123.42 km) |
| Donaueschingen to Otelu Rosu | 676.02 mi (1,087.96 km) |
| Donaueschingen to Otopeni | 869.44 mi (1,399.23 km) |
| Donaueschingen to Ovidiu | 990.68 mi (1,594.35 km) |
