| South San Francisco to Sestu | 6,294.16 mi (10,129.47 km) |
| South San Francisco to Settimo Torinese | 5,930.87 mi (9,544.82 km) |
| South San Francisco to Seveso | 5,942.60 mi (9,563.70 km) |
| South San Francisco to Sezze | 6,289.83 mi (10,122.50 km) |
| South San Francisco to Siano | 6,376.50 mi (10,261.99 km) |
| South San Francisco to Siena | 6,136.16 mi (9,875.20 km) |
| South San Francisco to Signa | 6,103.20 mi (9,822.15 km) |
| South San Francisco to Silea | 6,030.27 mi (9,704.78 km) |
| South San Francisco to Silvi Paese | 6,258.87 mi (10,072.68 km) |
| South San Francisco to Sinalunga | 6,153.46 mi (9,903.04 km) |
| South San Francisco to Siniscola | 6,241.94 mi (10,045.44 km) |
| South San Francisco to Sinnai | 6,297.51 mi (10,134.86 km) |
| South San Francisco to Siracusa | 6,611.19 mi (10,639.69 km) |
| South San Francisco to Solaro | 5,942.65 mi (9,563.76 km) |
| South San Francisco to Soliera | 6,044.24 mi (9,727.27 km) |
