| Castricum to Popovo | 1,176.27 mi (1,893.03 km) |
| Castricum to Provadia | 1,229.95 mi (1,979.42 km) |
| Castricum to Radnevo | 1,213.11 mi (1,952.31 km) |
| Castricum to Radomir | 1,092.03 mi (1,757.45 km) |
| Castricum to Rakitovo | 1,160.55 mi (1,867.73 km) |
| Castricum to Rakovski | 1,177.78 mi (1,895.45 km) |
| Castricum to Razgrad | 1,179.06 mi (1,897.51 km) |
| Castricum to Razlog | 1,143.54 mi (1,840.35 km) |
| Castricum to Ruse | 1,144.62 mi (1,842.09 km) |
| Castricum to Samokov | 1,124.17 mi (1,809.17 km) |
| Castricum to Sandanski | 1,152.99 mi (1,855.55 km) |
| Castricum to Sevlievo | 1,148.52 mi (1,848.36 km) |
| Castricum to Shumen | 1,206.18 mi (1,941.16 km) |
| Castricum to Silistra | 1,182.96 mi (1,903.79 km) |
| Castricum to Sliven | 1,210.31 mi (1,947.80 km) |
