| Watsonville to Karlovo | 6,550.88 mi (10,542.62 km) |
| Watsonville to Karnobat | 6,599.01 mi (10,620.07 km) |
| Watsonville to Kavarna | 6,576.40 mi (10,583.69 km) |
| Watsonville to Kazanlak | 6,565.76 mi (10,566.57 km) |
| Watsonville to Knezha | 6,481.62 mi (10,431.17 km) |
| Watsonville to Kostinbrod | 6,503.80 mi (10,466.86 km) |
| Watsonville to Kozloduy | 6,456.26 mi (10,390.34 km) |
| Watsonville to Kyustendil | 6,523.90 mi (10,499.20 km) |
| Watsonville to Levski | 6,513.26 mi (10,482.07 km) |
| Watsonville to Lom | 6,442.37 mi (10,368.00 km) |
| Watsonville to Lovech | 6,518.43 mi (10,490.40 km) |
| Watsonville to Lukovit | 6,502.02 mi (10,464.00 km) |
| Watsonville to Lyaskovets | 6,542.61 mi (10,529.32 km) |
| Watsonville to Mezdra | 6,494.49 mi (10,451.87 km) |
| Watsonville to Momchilgrad | 6,633.53 mi (10,675.63 km) |
