| Upminster to Nasaud | 1,119.38 mi (1,801.46 km) |
| Upminster to Navodari | 1,393.96 mi (2,243.36 km) |
| Upminster to Negresti-Oas | 1,061.27 mi (1,707.95 km) |
| Upminster to Nehoiu | 1,260.36 mi (2,028.35 km) |
| Upminster to Ocna Mures | 1,122.85 mi (1,807.05 km) |
| Upminster to Odobesti | 1,279.03 mi (2,058.40 km) |
| Upminster to Odorheiu Secuiesc | 1,186.48 mi (1,909.46 km) |
| Upminster to Oltenita | 1,319.18 mi (2,123.01 km) |
| Upminster to Onesti | 1,250.75 mi (2,012.89 km) |
| Upminster to Oradea | 1,019.65 mi (1,640.96 km) |
| Upminster to Orastie | 1,112.54 mi (1,790.46 km) |
| Upminster to Oravita | 1,077.95 mi (1,734.79 km) |
| Upminster to Orsova | 1,118.99 mi (1,800.84 km) |
| Upminster to Otelu Rosu | 1,088.42 mi (1,751.64 km) |
| Upminster to Otopeni | 1,278.48 mi (2,057.51 km) |
