| Slough to Popovo | 1,364.45 mi (2,195.87 km) |
| Slough to Provadia | 1,421.06 mi (2,286.97 km) |
| Slough to Radnevo | 1,393.66 mi (2,242.88 km) |
| Slough to Radomir | 1,261.56 mi (2,030.29 km) |
| Slough to Rakitovo | 1,331.35 mi (2,142.60 km) |
| Slough to Rakovski | 1,354.41 mi (2,179.71 km) |
| Slough to Razgrad | 1,369.31 mi (2,203.69 km) |
| Slough to Razlog | 1,310.80 mi (2,109.52 km) |
| Slough to Ruse | 1,334.82 mi (2,148.18 km) |
| Slough to Samokov | 1,295.00 mi (2,084.10 km) |
| Slough to Sandanski | 1,317.16 mi (2,119.77 km) |
| Slough to Sevlievo | 1,330.58 mi (2,141.35 km) |
| Slough to Shumen | 1,396.28 mi (2,247.09 km) |
| Slough to Silistra | 1,378.99 mi (2,219.27 km) |
| Slough to Sliven | 1,394.71 mi (2,244.58 km) |
