| Idar-Oberstein to Navodari | 1,065.82 mi (1,715.27 km) |
| Idar-Oberstein to Negresti-Oas | 742.83 mi (1,195.47 km) |
| Idar-Oberstein to Nehoiu | 932.72 mi (1,501.07 km) |
| Idar-Oberstein to Ocna Mures | 796.07 mi (1,281.15 km) |
| Idar-Oberstein to Odobesti | 954.27 mi (1,535.76 km) |
| Idar-Oberstein to Odorheiu Secuiesc | 861.58 mi (1,386.58 km) |
| Idar-Oberstein to Oltenita | 987.98 mi (1,590.00 km) |
| Idar-Oberstein to Onesti | 927.92 mi (1,493.34 km) |
| Idar-Oberstein to Oradea | 693.33 mi (1,115.80 km) |
| Idar-Oberstein to Orastie | 782.54 mi (1,259.38 km) |
| Idar-Oberstein to Oravita | 744.27 mi (1,197.79 km) |
| Idar-Oberstein to Orsova | 785.31 mi (1,263.84 km) |
| Idar-Oberstein to Otelu Rosu | 756.35 mi (1,217.23 km) |
| Idar-Oberstein to Otopeni | 947.87 mi (1,525.45 km) |
| Idar-Oberstein to Ovidiu | 1,065.16 mi (1,714.20 km) |
