| Ridderkerk to Popovo | 1,160.43 mi (1,867.52 km) |
| Ridderkerk to Provadia | 1,215.21 mi (1,955.68 km) |
| Ridderkerk to Radnevo | 1,194.81 mi (1,922.86 km) |
| Ridderkerk to Radomir | 1,070.25 mi (1,722.40 km) |
| Ridderkerk to Rakitovo | 1,139.26 mi (1,833.46 km) |
| Ridderkerk to Rakovski | 1,158.22 mi (1,863.98 km) |
| Ridderkerk to Razgrad | 1,163.94 mi (1,873.18 km) |
| Ridderkerk to Razlog | 1,121.23 mi (1,804.44 km) |
| Ridderkerk to Ruse | 1,129.43 mi (1,817.65 km) |
| Ridderkerk to Samokov | 1,102.82 mi (1,774.81 km) |
| Ridderkerk to Sandanski | 1,129.86 mi (1,818.33 km) |
| Ridderkerk to Sevlievo | 1,130.60 mi (1,819.52 km) |
| Ridderkerk to Shumen | 1,191.05 mi (1,916.80 km) |
| Ridderkerk to Silistra | 1,169.97 mi (1,882.88 km) |
| Ridderkerk to Sliven | 1,193.24 mi (1,920.34 km) |
