| Boulder City to Devnya | 6,486.59 mi (10,439.16 km) |
| Boulder City to Dimitrovgrad | 6,505.57 mi (10,469.70 km) |
| Boulder City to Dobrich | 6,472.16 mi (10,415.93 km) |
| Boulder City to Dospat | 6,490.41 mi (10,445.31 km) |
| Boulder City to Dupnitsa | 6,425.64 mi (10,341.06 km) |
| Boulder City to Elhovo | 6,523.98 mi (10,499.34 km) |
| Boulder City to Etropole | 6,416.68 mi (10,326.64 km) |
| Boulder City to Gabrovo | 6,450.26 mi (10,380.69 km) |
| Boulder City to Gorna Oryahovitsa | 6,444.07 mi (10,370.73 km) |
| Boulder City to Gotse Delchev | 6,483.31 mi (10,433.88 km) |
| Boulder City to Harmanli | 6,520.42 mi (10,493.59 km) |
| Boulder City to Haskovo | 6,511.59 mi (10,479.39 km) |
| Boulder City to Ihtiman | 6,434.81 mi (10,355.83 km) |
| Boulder City to Isperih | 6,438.31 mi (10,361.46 km) |
| Boulder City to Kardzhali | 6,522.99 mi (10,497.73 km) |
