| Merthyr Tudful to Jozefow | 1,043.68 mi (1,679.63 km) |
| Merthyr Tudful to Kalisz | 914.54 mi (1,471.82 km) |
| Merthyr Tudful to Kamien Pomorski | 770.44 mi (1,239.90 km) |
| Merthyr Tudful to Kamienna Gora | 839.36 mi (1,350.82 km) |
| Merthyr Tudful to Karczew | 1,044.88 mi (1,681.57 km) |
| Merthyr Tudful to Kartuzy | 910.34 mi (1,465.05 km) |
| Merthyr Tudful to Katowice | 975.10 mi (1,569.27 km) |
| Merthyr Tudful to Kedzierzyn-Kozle | 938.76 mi (1,510.79 km) |
| Merthyr Tudful to Kepno | 915.78 mi (1,473.81 km) |
| Merthyr Tudful to Ketrzyn | 1,038.76 mi (1,671.72 km) |
| Merthyr Tudful to Kety | 990.36 mi (1,593.83 km) |
| Merthyr Tudful to Kielce | 1,034.13 mi (1,664.28 km) |
| Merthyr Tudful to Kielczow | 883.33 mi (1,421.58 km) |
| Merthyr Tudful to Klobuck | 961.15 mi (1,546.81 km) |
| Merthyr Tudful to Klodzko | 871.12 mi (1,401.92 km) |
