| Ottumwa to Smolyan | 5,508.54 mi (8,865.15 km) |
| Ottumwa to Sofia | 5,404.27 mi (8,697.33 km) |
| Ottumwa to Sopot | 5,456.47 mi (8,781.35 km) |
| Ottumwa to Sozopol | 5,569.44 mi (8,963.15 km) |
| Ottumwa to Sredets | 5,555.96 mi (8,941.46 km) |
| Ottumwa to Stamboliyski | 5,474.94 mi (8,811.07 km) |
| Ottumwa to Stara Zagora | 5,498.62 mi (8,849.17 km) |
| Ottumwa to Svilengrad | 5,551.64 mi (8,934.51 km) |
| Ottumwa to Svishtov | 5,428.30 mi (8,736.01 km) |
| Ottumwa to Targovishte | 5,488.81 mi (8,833.39 km) |
| Ottumwa to Teteven | 5,426.25 mi (8,732.71 km) |
| Ottumwa to Troyan | 5,443.56 mi (8,760.57 km) |
| Ottumwa to Tryavna | 5,471.43 mi (8,805.41 km) |
| Ottumwa to Tutrakan | 5,448.99 mi (8,769.30 km) |
| Ottumwa to Varna | 5,535.24 mi (8,908.11 km) |
