| Serris to Karlovo | 1,140.05 mi (1,834.74 km) |
| Serris to Karnobat | 1,236.98 mi (1,990.72 km) |
| Serris to Kavarna | 1,272.13 mi (2,047.30 km) |
| Serris to Kazanlak | 1,167.18 mi (1,878.39 km) |
| Serris to Knezha | 1,079.65 mi (1,737.52 km) |
| Serris to Kostinbrod | 1,064.12 mi (1,712.53 km) |
| Serris to Kozloduy | 1,055.15 mi (1,698.10 km) |
| Serris to Kyustendil | 1,059.95 mi (1,705.83 km) |
| Serris to Levski | 1,130.65 mi (1,819.60 km) |
| Serris to Lom | 1,031.76 mi (1,660.46 km) |
| Serris to Lovech | 1,119.62 mi (1,801.85 km) |
| Serris to Lukovit | 1,093.06 mi (1,759.11 km) |
| Serris to Lyaskovets | 1,165.22 mi (1,875.23 km) |
| Serris to Mezdra | 1,074.06 mi (1,728.53 km) |
| Serris to Momchilgrad | 1,206.44 mi (1,941.57 km) |
