| South River to Popovo | 4,830.67 mi (7,774.21 km) |
| South River to Provadia | 4,885.56 mi (7,862.54 km) |
| South River to Radnevo | 4,862.52 mi (7,825.47 km) |
| South River to Radomir | 4,730.01 mi (7,612.22 km) |
| South River to Rakitovo | 4,799.90 mi (7,724.69 km) |
| South River to Rakovski | 4,823.56 mi (7,762.76 km) |
| South River to Razgrad | 4,834.32 mi (7,780.09 km) |
| South River to Razlog | 4,778.48 mi (7,690.22 km) |
| South River to Ruse | 4,799.81 mi (7,724.55 km) |
| South River to Samokov | 4,763.64 mi (7,666.34 km) |
| South River to Sandanski | 4,783.68 mi (7,698.59 km) |
| South River to Sevlievo | 4,799.07 mi (7,723.35 km) |
| South River to Shumen | 4,861.42 mi (7,823.71 km) |
| South River to Silistra | 4,839.26 mi (7,788.03 km) |
| South River to Sliven | 4,862.62 mi (7,825.63 km) |
