| Houghton Regis to Karlovo | 1,339.15 mi (2,155.16 km) |
| Houghton Regis to Karnobat | 1,428.24 mi (2,298.53 km) |
| Houghton Regis to Kavarna | 1,452.36 mi (2,337.35 km) |
| Houghton Regis to Kazanlak | 1,364.29 mi (2,195.61 km) |
| Houghton Regis to Knezha | 1,274.58 mi (2,051.24 km) |
| Houghton Regis to Kostinbrod | 1,267.90 mi (2,040.48 km) |
| Houghton Regis to Kozloduy | 1,248.97 mi (2,010.02 km) |
| Houghton Regis to Kyustendil | 1,269.77 mi (2,043.49 km) |
| Houghton Regis to Levski | 1,322.78 mi (2,128.81 km) |
| Houghton Regis to Lom | 1,227.10 mi (1,974.83 km) |
| Houghton Regis to Lovech | 1,315.19 mi (2,116.60 km) |
| Houghton Regis to Lukovit | 1,290.17 mi (2,076.32 km) |
| Houghton Regis to Lyaskovets | 1,357.39 mi (2,184.51 km) |
| Houghton Regis to Mezdra | 1,273.34 mi (2,049.25 km) |
| Houghton Regis to Momchilgrad | 1,411.25 mi (2,271.18 km) |
