| Willebroek to Navodari | 1,213.07 mi (1,952.25 km) |
| Willebroek to Negresti-Oas | 881.01 mi (1,417.84 km) |
| Willebroek to Nehoiu | 1,079.46 mi (1,737.22 km) |
| Willebroek to Ocna Mures | 941.94 mi (1,515.91 km) |
| Willebroek to Odobesti | 1,098.20 mi (1,767.39 km) |
| Willebroek to Odorheiu Secuiesc | 1,005.63 mi (1,618.41 km) |
| Willebroek to Oltenita | 1,138.65 mi (1,832.48 km) |
| Willebroek to Onesti | 1,070.07 mi (1,722.10 km) |
| Willebroek to Oradea | 838.74 mi (1,349.83 km) |
| Willebroek to Orastie | 931.85 mi (1,499.67 km) |
| Willebroek to Oravita | 898.70 mi (1,446.31 km) |
| Willebroek to Orsova | 939.72 mi (1,512.33 km) |
| Willebroek to Otelu Rosu | 908.23 mi (1,461.65 km) |
| Willebroek to Otopeni | 1,097.84 mi (1,766.81 km) |
| Willebroek to Ovidiu | 1,212.65 mi (1,951.57 km) |
