| Naperville to Karlovo | 5,271.66 mi (8,483.92 km) |
| Naperville to Karnobat | 5,349.54 mi (8,609.26 km) |
| Naperville to Kavarna | 5,356.33 mi (8,620.18 km) |
| Naperville to Kazanlak | 5,294.22 mi (8,520.23 km) |
| Naperville to Knezha | 5,204.06 mi (8,375.13 km) |
| Naperville to Kostinbrod | 5,205.75 mi (8,377.84 km) |
| Naperville to Kozloduy | 5,177.86 mi (8,332.97 km) |
| Naperville to Kyustendil | 5,211.83 mi (8,387.62 km) |
| Naperville to Levski | 5,247.96 mi (8,445.77 km) |
| Naperville to Lom | 5,158.07 mi (8,301.10 km) |
| Naperville to Lovech | 5,244.47 mi (8,440.15 km) |
| Naperville to Lukovit | 5,221.58 mi (8,403.32 km) |
| Naperville to Lyaskovets | 5,281.72 mi (8,500.10 km) |
| Naperville to Mezdra | 5,207.20 mi (8,380.18 km) |
| Naperville to Momchilgrad | 5,348.15 mi (8,607.02 km) |
