| South San Francisco to Karlovo | 6,518.89 mi (10,491.13 km) |
| South San Francisco to Karnobat | 6,565.68 mi (10,566.44 km) |
| South San Francisco to Kavarna | 6,541.96 mi (10,528.26 km) |
| South San Francisco to Kazanlak | 6,533.42 mi (10,514.52 km) |
| South San Francisco to Knezha | 6,449.72 mi (10,379.83 km) |
| South San Francisco to Kostinbrod | 6,472.72 mi (10,416.83 km) |
| South San Francisco to Kozloduy | 6,424.45 mi (10,339.15 km) |
| South San Francisco to Kyustendil | 6,493.37 mi (10,450.07 km) |
| South San Francisco to Levski | 6,480.77 mi (10,429.80 km) |
| South San Francisco to Lom | 6,410.84 mi (10,317.26 km) |
| South San Francisco to Lovech | 6,486.29 mi (10,438.68 km) |
| South San Francisco to Lukovit | 6,470.20 mi (10,412.78 km) |
| South San Francisco to Lyaskovets | 6,509.88 mi (10,476.64 km) |
| South San Francisco to Mezdra | 6,462.96 mi (10,401.14 km) |
| South San Francisco to Momchilgrad | 6,601.60 mi (10,624.25 km) |
