| Harpenden to Sinop | 1,784.95 mi (2,872.59 km) |
| Harpenden to Siran | 2,027.09 mi (3,262.29 km) |
| Harpenden to Sirnak | 2,281.98 mi (3,672.49 km) |
| Harpenden to Sirvan | 2,239.97 mi (3,604.89 km) |
| Harpenden to Sivas | 1,956.42 mi (3,148.55 km) |
| Harpenden to Sivasli | 1,710.84 mi (2,753.33 km) |
| Harpenden to Siverek | 2,139.60 mi (3,443.35 km) |
| Harpenden to Sivrice | 2,108.79 mi (3,393.76 km) |
| Harpenden to Sivrihisar | 1,741.91 mi (2,803.33 km) |
| Harpenden to Sogut | 1,661.38 mi (2,673.73 km) |
| Harpenden to Sogutlu | 1,635.65 mi (2,632.32 km) |
| Harpenden to Soke | 1,656.27 mi (2,665.50 km) |
| Harpenden to Solhan | 2,159.85 mi (3,475.94 km) |
| Harpenden to Soma | 1,595.52 mi (2,567.74 km) |
| Harpenden to Sorgun | 1,877.16 mi (3,021.00 km) |
