| Sioux City to Sestu | 5,113.22 mi (8,228.93 km) |
| Sioux City to Settimo Torinese | 4,796.22 mi (7,718.78 km) |
| Sioux City to Seveso | 4,823.90 mi (7,763.32 km) |
| Sioux City to Sezze | 5,162.06 mi (8,307.53 km) |
| Sioux City to Siano | 5,256.29 mi (8,459.18 km) |
| Sioux City to Siena | 5,011.51 mi (8,065.25 km) |
| Sioux City to Signa | 4,981.27 mi (8,016.58 km) |
| Sioux City to Silea | 4,937.35 mi (7,945.90 km) |
| Sioux City to Silvi Paese | 5,150.34 mi (8,288.67 km) |
| Sioux City to Sinalunga | 5,031.13 mi (8,096.82 km) |
| Sioux City to Siniscola | 5,077.55 mi (8,171.53 km) |
| Sioux City to Sinnai | 5,117.47 mi (8,235.77 km) |
| Sioux City to Siracusa | 5,462.10 mi (8,790.40 km) |
| Sioux City to Solaro | 4,823.23 mi (7,762.23 km) |
| Sioux City to Soliera | 4,930.53 mi (7,934.93 km) |
