| Sluis to Navodari | 1,258.19 mi (2,024.85 km) |
| Sluis to Negresti-Oas | 925.20 mi (1,488.97 km) |
| Sluis to Nehoiu | 1,124.55 mi (1,809.79 km) |
| Sluis to Ocna Mures | 986.99 mi (1,588.40 km) |
| Sluis to Odobesti | 1,142.99 mi (1,839.46 km) |
| Sluis to Odorheiu Secuiesc | 1,050.46 mi (1,690.55 km) |
| Sluis to Oltenita | 1,184.08 mi (1,905.59 km) |
| Sluis to Onesti | 1,114.65 mi (1,793.86 km) |
| Sluis to Oradea | 883.78 mi (1,422.31 km) |
| Sluis to Orastie | 977.21 mi (1,572.66 km) |
| Sluis to Oravita | 944.32 mi (1,519.73 km) |
| Sluis to Orsova | 985.34 mi (1,585.75 km) |
| Sluis to Otelu Rosu | 953.76 mi (1,534.92 km) |
| Sluis to Otopeni | 1,143.22 mi (1,839.84 km) |
| Sluis to Ovidiu | 1,257.79 mi (2,024.22 km) |
