| Halden to Navodari | 1,250.63 mi (2,012.69 km) |
| Halden to Negresti-Oas | 916.64 mi (1,475.20 km) |
| Halden to Nehoiu | 1,134.08 mi (1,825.13 km) |
| Halden to Ocna Mures | 1,017.22 mi (1,637.06 km) |
| Halden to Odobesti | 1,126.59 mi (1,813.07 km) |
| Halden to Odorheiu Secuiesc | 1,052.85 mi (1,694.40 km) |
| Halden to Oltenita | 1,219.46 mi (1,962.53 km) |
| Halden to Onesti | 1,089.99 mi (1,754.16 km) |
| Halden to Oradea | 936.20 mi (1,506.67 km) |
| Halden to Orastie | 1,037.93 mi (1,670.39 km) |
| Halden to Oravita | 1,062.51 mi (1,709.95 km) |
| Halden to Orsova | 1,095.06 mi (1,762.33 km) |
| Halden to Otelu Rosu | 1,043.23 mi (1,678.92 km) |
| Halden to Otopeni | 1,178.37 mi (1,896.40 km) |
| Halden to Ovidiu | 1,252.43 mi (2,015.60 km) |
