| Rockford to Karlovo | 5,278.26 mi (8,494.54 km) |
| Rockford to Karnobat | 5,354.96 mi (8,617.97 km) |
| Rockford to Kavarna | 5,360.43 mi (8,626.78 km) |
| Rockford to Kazanlak | 5,300.52 mi (8,530.36 km) |
| Rockford to Knezha | 5,210.42 mi (8,385.36 km) |
| Rockford to Kostinbrod | 5,213.08 mi (8,389.64 km) |
| Rockford to Kozloduy | 5,184.20 mi (8,343.17 km) |
| Rockford to Kyustendil | 5,219.84 mi (8,400.51 km) |
| Rockford to Levski | 5,253.85 mi (8,455.26 km) |
| Rockford to Lom | 5,164.63 mi (8,311.67 km) |
| Rockford to Lovech | 5,250.76 mi (8,450.28 km) |
| Rockford to Lukovit | 5,228.12 mi (8,413.84 km) |
| Rockford to Lyaskovets | 5,287.49 mi (8,509.40 km) |
| Rockford to Mezdra | 5,214.03 mi (8,391.17 km) |
| Rockford to Momchilgrad | 5,355.22 mi (8,618.39 km) |
