| Southborough to Sestu | 923.66 mi (1,486.49 km) |
| Southborough to Settimo Torinese | 540.70 mi (870.18 km) |
| Southborough to Seveso | 556.87 mi (896.20 km) |
| Southborough to Sezze | 902.14 mi (1,451.86 km) |
| Southborough to Siano | 992.59 mi (1,597.42 km) |
| Southborough to Siena | 748.78 mi (1,205.05 km) |
| Southborough to Signa | 716.79 mi (1,153.57 km) |
| Southborough to Silea | 668.92 mi (1,076.52 km) |
| Southborough to Silvi Paese | 881.78 mi (1,419.10 km) |
| Southborough to Sinalunga | 767.17 mi (1,234.65 km) |
| Southborough to Siniscola | 859.14 mi (1,382.65 km) |
| Southborough to Sinnai | 925.95 mi (1,490.18 km) |
| Southborough to Siracusa | 1,221.01 mi (1,965.02 km) |
| Southborough to Solaro | 556.52 mi (895.63 km) |
| Southborough to Soliera | 662.29 mi (1,065.85 km) |
