| Castellana Grotte to Navodari | 628.04 mi (1,010.74 km) |
| Castellana Grotte to Negresti-Oas | 572.70 mi (921.67 km) |
| Castellana Grotte to Nehoiu | 554.25 mi (891.98 km) |
| Castellana Grotte to Ocna Mures | 506.36 mi (814.91 km) |
| Castellana Grotte to Odobesti | 600.52 mi (966.44 km) |
| Castellana Grotte to Odorheiu Secuiesc | 553.07 mi (890.07 km) |
| Castellana Grotte to Oltenita | 530.44 mi (853.66 km) |
| Castellana Grotte to Onesti | 606.73 mi (976.43 km) |
| Castellana Grotte to Oradea | 488.37 mi (785.96 km) |
| Castellana Grotte to Orastie | 457.55 mi (736.35 km) |
| Castellana Grotte to Oravita | 366.88 mi (590.44 km) |
| Castellana Grotte to Orsova | 375.00 mi (603.50 km) |
| Castellana Grotte to Otelu Rosu | 413.09 mi (664.80 km) |
| Castellana Grotte to Otopeni | 517.71 mi (833.17 km) |
| Castellana Grotte to Ovidiu | 624.44 mi (1,004.94 km) |
