| Hellevoetsluis to Navodari | 1,235.44 mi (1,988.25 km) |
| Hellevoetsluis to Negresti-Oas | 898.66 mi (1,446.26 km) |
| Hellevoetsluis to Nehoiu | 1,101.75 mi (1,773.10 km) |
| Hellevoetsluis to Ocna Mures | 964.04 mi (1,551.48 km) |
| Hellevoetsluis to Odobesti | 1,118.58 mi (1,800.18 km) |
| Hellevoetsluis to Odorheiu Secuiesc | 1,026.34 mi (1,651.74 km) |
| Hellevoetsluis to Oltenita | 1,163.73 mi (1,872.84 km) |
| Hellevoetsluis to Onesti | 1,089.39 mi (1,753.21 km) |
| Hellevoetsluis to Oradea | 860.92 mi (1,385.51 km) |
| Hellevoetsluis to Orastie | 956.37 mi (1,539.14 km) |
| Hellevoetsluis to Oravita | 927.52 mi (1,492.70 km) |
| Hellevoetsluis to Orsova | 968.43 mi (1,558.53 km) |
| Hellevoetsluis to Otelu Rosu | 934.80 mi (1,504.42 km) |
| Hellevoetsluis to Otopeni | 1,122.45 mi (1,806.42 km) |
| Hellevoetsluis to Ovidiu | 1,235.19 mi (1,987.85 km) |
