| Sleaford to Popovo | 1,385.50 mi (2,229.74 km) |
| Sleaford to Provadia | 1,440.20 mi (2,317.77 km) |
| Sleaford to Radnevo | 1,419.65 mi (2,284.70 km) |
| Sleaford to Radomir | 1,293.74 mi (2,082.07 km) |
| Sleaford to Rakitovo | 1,362.98 mi (2,193.50 km) |
| Sleaford to Rakovski | 1,382.70 mi (2,225.24 km) |
| Sleaford to Razgrad | 1,388.97 mi (2,235.33 km) |
| Sleaford to Razlog | 1,344.35 mi (2,163.52 km) |
| Sleaford to Ruse | 1,354.47 mi (2,179.80 km) |
| Sleaford to Samokov | 1,326.53 mi (2,134.84 km) |
| Sleaford to Sandanski | 1,352.40 mi (2,176.47 km) |
| Sleaford to Sevlievo | 1,355.52 mi (2,181.50 km) |
| Sleaford to Shumen | 1,416.08 mi (2,278.96 km) |
| Sleaford to Silistra | 1,394.59 mi (2,244.37 km) |
| Sleaford to Sliven | 1,418.27 mi (2,282.49 km) |
