| Irthlingborough to Ilawa | 841.59 mi (1,354.41 km) |
| Irthlingborough to Imielin | 868.40 mi (1,397.56 km) |
| Irthlingborough to Inowroclaw | 791.24 mi (1,273.37 km) |
| Irthlingborough to Janow Lubelski | 992.09 mi (1,596.61 km) |
| Irthlingborough to Jarocin | 766.42 mi (1,233.44 km) |
| Irthlingborough to Jaroslaw | 1,017.04 mi (1,636.76 km) |
| Irthlingborough to Jasien | 800.70 mi (1,288.61 km) |
| Irthlingborough to Jaslo | 971.95 mi (1,564.20 km) |
| Irthlingborough to Jastrzebie-Zdroj | 845.62 mi (1,360.90 km) |
| Irthlingborough to Jawor | 723.92 mi (1,165.03 km) |
| Irthlingborough to Jaworzno | 869.17 mi (1,398.80 km) |
| Irthlingborough to Jedrzejow | 904.28 mi (1,455.31 km) |
| Irthlingborough to Jelcz-Laskowice | 772.04 mi (1,242.49 km) |
| Irthlingborough to Jelenia Gora | 706.70 mi (1,137.32 km) |
| Irthlingborough to Jozefoslaw | 913.71 mi (1,470.48 km) |
