| Niagara Falls to Sinop | 5,278.09 mi (8,494.27 km) |
| Niagara Falls to Siran | 5,510.96 mi (8,869.04 km) |
| Niagara Falls to Sirnak | 5,767.41 mi (9,281.74 km) |
| Niagara Falls to Sirvan | 5,723.40 mi (9,210.93 km) |
| Niagara Falls to Sivas | 5,459.83 mi (8,786.75 km) |
| Niagara Falls to Sivasli | 5,251.29 mi (8,451.13 km) |
| Niagara Falls to Siverek | 5,645.43 mi (9,085.44 km) |
| Niagara Falls to Sivrice | 5,608.67 mi (9,026.28 km) |
| Niagara Falls to Sivrihisar | 5,274.71 mi (8,488.82 km) |
| Niagara Falls to Sogut | 5,195.92 mi (8,362.03 km) |
| Niagara Falls to Sogutlu | 5,164.57 mi (8,311.57 km) |
| Niagara Falls to Soke | 5,197.67 mi (8,364.85 km) |
| Niagara Falls to Solhan | 5,641.68 mi (9,079.40 km) |
| Niagara Falls to Soma | 5,137.11 mi (8,267.39 km) |
| Niagara Falls to Sorgun | 5,391.12 mi (8,676.17 km) |
