| Boulder to Sestu | 5,569.99 mi (8,964.03 km) |
| Boulder to Settimo Torinese | 5,240.30 mi (8,433.45 km) |
| Boulder to Seveso | 5,264.00 mi (8,471.58 km) |
| Boulder to Sezze | 5,606.02 mi (9,022.01 km) |
| Boulder to Siano | 5,698.76 mi (9,171.28 km) |
| Boulder to Siena | 5,454.01 mi (8,777.38 km) |
| Boulder to Signa | 5,422.93 mi (8,727.37 km) |
| Boulder to Silea | 5,371.27 mi (8,644.22 km) |
| Boulder to Silvi Paese | 5,589.36 mi (8,995.21 km) |
| Boulder to Sinalunga | 5,473.13 mi (8,808.14 km) |
| Boulder to Siniscola | 5,530.22 mi (8,900.02 km) |
| Boulder to Sinnai | 5,574.04 mi (8,970.55 km) |
| Boulder to Siracusa | 5,912.55 mi (9,515.34 km) |
| Boulder to Solaro | 5,263.51 mi (8,470.79 km) |
| Boulder to Soliera | 5,369.84 mi (8,641.93 km) |
