| Castel Gandolfo to Popovo | 699.32 mi (1,125.44 km) |
| Castel Gandolfo to Provadia | 758.89 mi (1,221.32 km) |
| Castel Gandolfo to Radnevo | 682.08 mi (1,097.70 km) |
| Castel Gandolfo to Radomir | 530.11 mi (853.13 km) |
| Castel Gandolfo to Rakitovo | 587.99 mi (946.28 km) |
| Castel Gandolfo to Rakovski | 632.64 mi (1,018.13 km) |
| Castel Gandolfo to Razgrad | 714.55 mi (1,149.96 km) |
| Castel Gandolfo to Razlog | 556.62 mi (895.80 km) |
| Castel Gandolfo to Ruse | 688.79 mi (1,108.50 km) |
| Castel Gandolfo to Samokov | 560.58 mi (902.17 km) |
| Castel Gandolfo to Sandanski | 548.55 mi (882.81 km) |
| Castel Gandolfo to Sevlievo | 641.45 mi (1,032.31 km) |
| Castel Gandolfo to Shumen | 734.11 mi (1,181.43 km) |
| Castel Gandolfo to Silistra | 755.85 mi (1,216.43 km) |
| Castel Gandolfo to Sliven | 702.32 mi (1,130.27 km) |
