| Letterkenny to Popovo | 1,708.03 mi (2,748.82 km) |
| Letterkenny to Provadia | 1,761.75 mi (2,835.27 km) |
| Letterkenny to Radnevo | 1,743.97 mi (2,806.65 km) |
| Letterkenny to Radomir | 1,619.55 mi (2,606.42 km) |
| Letterkenny to Rakitovo | 1,688.68 mi (2,717.66 km) |
| Letterkenny to Rakovski | 1,707.71 mi (2,748.29 km) |
| Letterkenny to Razgrad | 1,710.87 mi (2,753.39 km) |
| Letterkenny to Razlog | 1,670.31 mi (2,688.11 km) |
| Letterkenny to Ruse | 1,676.43 mi (2,697.96 km) |
| Letterkenny to Samokov | 1,652.23 mi (2,659.01 km) |
| Letterkenny to Sandanski | 1,678.50 mi (2,701.28 km) |
| Letterkenny to Sevlievo | 1,679.58 mi (2,703.03 km) |
| Letterkenny to Shumen | 1,738.00 mi (2,797.03 km) |
| Letterkenny to Silistra | 1,714.37 mi (2,759.01 km) |
| Letterkenny to Sliven | 1,741.77 mi (2,803.10 km) |
