| Boppard to Karlovo | 969.52 mi (1,560.29 km) |
| Boppard to Karnobat | 1,057.69 mi (1,702.19 km) |
| Boppard to Kavarna | 1,082.31 mi (1,741.80 km) |
| Boppard to Kazanlak | 994.30 mi (1,600.17 km) |
| Boppard to Knezha | 904.43 mi (1,455.54 km) |
| Boppard to Kostinbrod | 899.52 mi (1,447.64 km) |
| Boppard to Kozloduy | 878.73 mi (1,414.18 km) |
| Boppard to Kyustendil | 903.49 mi (1,454.02 km) |
| Boppard to Levski | 952.33 mi (1,532.63 km) |
| Boppard to Lom | 857.08 mi (1,379.34 km) |
| Boppard to Lovech | 945.07 mi (1,520.94 km) |
| Boppard to Lukovit | 920.29 mi (1,481.06 km) |
| Boppard to Lyaskovets | 986.92 mi (1,588.29 km) |
| Boppard to Mezdra | 903.88 mi (1,454.65 km) |
| Boppard to Momchilgrad | 1,042.74 mi (1,678.14 km) |
