| Castel Bolognese to Popovo | 721.52 mi (1,161.18 km) |
| Castel Bolognese to Provadia | 782.98 mi (1,260.09 km) |
| Castel Bolognese to Radnevo | 723.15 mi (1,163.80 km) |
| Castel Bolognese to Radomir | 572.11 mi (920.73 km) |
| Castel Bolognese to Rakitovo | 639.13 mi (1,028.59 km) |
| Castel Bolognese to Rakovski | 675.86 mi (1,087.70 km) |
| Castel Bolognese to Razgrad | 733.37 mi (1,180.25 km) |
| Castel Bolognese to Razlog | 611.51 mi (984.13 km) |
| Castel Bolognese to Ruse | 702.59 mi (1,130.72 km) |
| Castel Bolognese to Samokov | 605.89 mi (975.09 km) |
| Castel Bolognese to Sandanski | 610.40 mi (982.35 km) |
| Castel Bolognese to Sevlievo | 670.54 mi (1,079.13 km) |
| Castel Bolognese to Shumen | 756.96 mi (1,218.21 km) |
| Castel Bolognese to Silistra | 764.59 mi (1,230.49 km) |
| Castel Bolognese to Sliven | 736.07 mi (1,184.59 km) |
