| South Portland to Solofra | 4,156.69 mi (6,689.54 km) |
| South Portland to Somma Lombardo | 3,718.86 mi (5,984.92 km) |
| South Portland to Somma Vesuviana | 4,137.22 mi (6,658.21 km) |
| South Portland to Sommacampagna | 3,819.38 mi (6,146.70 km) |
| South Portland to Sona | 3,817.54 mi (6,143.74 km) |
| South Portland to Sondrio | 3,752.28 mi (6,038.71 km) |
| South Portland to Sora | 4,069.66 mi (6,549.48 km) |
| South Portland to Sorbolo | 3,821.27 mi (6,149.73 km) |
| South Portland to Soresina | 3,781.18 mi (6,085.23 km) |
| South Portland to Sorisole | 3,757.60 mi (6,047.28 km) |
| South Portland to Sorrento | 4,143.82 mi (6,668.83 km) |
| South Portland to Sorso | 3,881.34 mi (6,246.42 km) |
| South Portland to Sortino | 4,308.76 mi (6,934.27 km) |
| South Portland to Soverato Marina | 4,315.34 mi (6,944.87 km) |
| South Portland to Sovicille | 3,909.40 mi (6,291.58 km) |
