| Gourock to Popovo | 1,618.65 mi (2,604.96 km) |
| Gourock to Provadia | 1,670.49 mi (2,688.40 km) |
| Gourock to Radnevo | 1,658.50 mi (2,669.09 km) |
| Gourock to Radomir | 1,540.19 mi (2,478.69 km) |
| Gourock to Rakitovo | 1,608.43 mi (2,588.52 km) |
| Gourock to Rakovski | 1,624.42 mi (2,614.26 km) |
| Gourock to Razgrad | 1,620.34 mi (2,607.69 km) |
| Gourock to Razlog | 1,591.90 mi (2,561.91 km) |
| Gourock to Ruse | 1,586.11 mi (2,552.59 km) |
| Gourock to Samokov | 1,572.10 mi (2,530.04 km) |
| Gourock to Sandanski | 1,601.58 mi (2,577.49 km) |
| Gourock to Sevlievo | 1,593.60 mi (2,564.65 km) |
| Gourock to Shumen | 1,647.41 mi (2,651.26 km) |
| Gourock to Silistra | 1,620.59 mi (2,608.09 km) |
| Gourock to Sliven | 1,654.25 mi (2,662.26 km) |
