| Hillsborough to Karlovo | 4,810.87 mi (7,742.35 km) |
| Hillsborough to Karnobat | 4,899.14 mi (7,884.40 km) |
| Hillsborough to Kavarna | 4,918.47 mi (7,915.52 km) |
| Hillsborough to Kazanlak | 4,836.05 mi (7,782.88 km) |
| Hillsborough to Knezha | 4,746.29 mi (7,638.41 km) |
| Hillsborough to Kostinbrod | 4,738.83 mi (7,626.41 km) |
| Hillsborough to Kozloduy | 4,720.61 mi (7,597.09 km) |
| Hillsborough to Kyustendil | 4,738.48 mi (7,625.85 km) |
| Hillsborough to Levski | 4,794.10 mi (7,715.36 km) |
| Hillsborough to Lom | 4,698.86 mi (7,562.08 km) |
| Hillsborough to Lovech | 4,786.91 mi (7,703.79 km) |
| Hillsborough to Lukovit | 4,761.93 mi (7,663.59 km) |
| Hillsborough to Lyaskovets | 4,828.65 mi (7,770.95 km) |
| Hillsborough to Mezdra | 4,745.01 mi (7,636.36 km) |
| Hillsborough to Momchilgrad | 4,882.14 mi (7,857.04 km) |
