| Monaghan to Smolyan | 1,686.81 mi (2,714.65 km) |
| Monaghan to Sofia | 1,583.13 mi (2,547.80 km) |
| Monaghan to Sopot | 1,640.21 mi (2,639.67 km) |
| Monaghan to Sozopol | 1,765.76 mi (2,841.71 km) |
| Monaghan to Sredets | 1,749.08 mi (2,814.87 km) |
| Monaghan to Stamboliyski | 1,655.14 mi (2,663.69 km) |
| Monaghan to Stara Zagora | 1,684.85 mi (2,711.50 km) |
| Monaghan to Svilengrad | 1,736.27 mi (2,794.25 km) |
| Monaghan to Svishtov | 1,621.32 mi (2,609.27 km) |
| Monaghan to Targovishte | 1,685.54 mi (2,712.61 km) |
| Monaghan to Teteven | 1,609.60 mi (2,590.40 km) |
| Monaghan to Troyan | 1,628.54 mi (2,620.89 km) |
| Monaghan to Tryavna | 1,659.77 mi (2,671.14 km) |
| Monaghan to Tutrakan | 1,652.93 mi (2,660.14 km) |
| Monaghan to Varna | 1,739.58 mi (2,799.58 km) |
