| Greenock to Nasaud | 1,373.60 mi (2,210.59 km) |
| Greenock to Navodari | 1,659.66 mi (2,670.96 km) |
| Greenock to Negresti-Oas | 1,312.73 mi (2,112.64 km) |
| Greenock to Nehoiu | 1,527.30 mi (2,457.95 km) |
| Greenock to Ocna Mures | 1,390.91 mi (2,238.46 km) |
| Greenock to Odobesti | 1,537.72 mi (2,474.71 km) |
| Greenock to Odorheiu Secuiesc | 1,447.95 mi (2,330.25 km) |
| Greenock to Oltenita | 1,596.92 mi (2,570.00 km) |
| Greenock to Onesti | 1,505.44 mi (2,422.76 km) |
| Greenock to Oradea | 1,289.71 mi (2,075.59 km) |
| Greenock to Orastie | 1,390.27 mi (2,237.43 km) |
| Greenock to Oravita | 1,372.36 mi (2,208.60 km) |
| Greenock to Orsova | 1,412.67 mi (2,273.47 km) |
| Greenock to Otelu Rosu | 1,374.29 mi (2,211.71 km) |
| Greenock to Otopeni | 1,554.71 mi (2,502.06 km) |
