| South Portland to Sinop | 4,933.93 mi (7,940.39 km) |
| South Portland to Siran | 5,171.13 mi (8,322.13 km) |
| South Portland to Sirnak | 5,428.31 mi (8,736.03 km) |
| South Portland to Sirvan | 5,384.80 mi (8,666.00 km) |
| South Portland to Sivas | 5,112.74 mi (8,228.16 km) |
| South Portland to Sivasli | 4,881.75 mi (7,856.42 km) |
| South Portland to Siverek | 5,298.03 mi (8,526.36 km) |
| South Portland to Sivrice | 5,263.53 mi (8,470.84 km) |
| South Portland to Sivrihisar | 4,912.68 mi (7,906.20 km) |
| South Portland to Sogut | 4,832.55 mi (7,777.24 km) |
| South Portland to Sogutlu | 4,804.89 mi (7,732.72 km) |
| South Portland to Soke | 4,820.74 mi (7,758.22 km) |
| South Portland to Solhan | 5,303.22 mi (8,534.70 km) |
| South Portland to Soma | 4,765.15 mi (7,668.77 km) |
| South Portland to Sorgun | 5,039.43 mi (8,110.18 km) |
