| Irthlingborough to Nasaud | 1,162.09 mi (1,870.21 km) |
| Irthlingborough to Navodari | 1,439.75 mi (2,317.05 km) |
| Irthlingborough to Negresti-Oas | 1,103.20 mi (1,775.43 km) |
| Irthlingborough to Nehoiu | 1,306.06 mi (2,101.90 km) |
| Irthlingborough to Ocna Mures | 1,168.36 mi (1,880.30 km) |
| Irthlingborough to Odobesti | 1,323.16 mi (2,129.41 km) |
| Irthlingborough to Odorheiu Secuiesc | 1,230.88 mi (1,980.91 km) |
| Irthlingborough to Oltenita | 1,367.15 mi (2,200.21 km) |
| Irthlingborough to Onesti | 1,294.00 mi (2,082.50 km) |
| Irthlingborough to Oradea | 1,065.20 mi (1,714.27 km) |
| Irthlingborough to Orastie | 1,159.97 mi (1,866.79 km) |
| Irthlingborough to Oravita | 1,128.66 mi (1,816.40 km) |
| Irthlingborough to Orsova | 1,169.66 mi (1,882.38 km) |
| Irthlingborough to Otelu Rosu | 1,137.42 mi (1,830.50 km) |
| Irthlingborough to Otopeni | 1,326.06 mi (2,134.08 km) |
