| Niagara Falls to Sesimbra | 3,565.08 mi (5,737.44 km) |
| Niagara Falls to Setubal | 3,572.18 mi (5,748.87 km) |
| Niagara Falls to Sever do Vouga | 3,524.56 mi (5,672.23 km) |
| Niagara Falls to Silves | 3,639.19 mi (5,856.71 km) |
| Niagara Falls to Sines | 3,592.69 mi (5,781.87 km) |
| Niagara Falls to Sintra | 3,539.60 mi (5,696.43 km) |
| Niagara Falls to Sobrado de Paiva | 3,519.63 mi (5,664.30 km) |
| Niagara Falls to Sobral de Monte Agraco | 3,543.53 mi (5,702.76 km) |
| Niagara Falls to Soure | 3,534.14 mi (5,687.65 km) |
| Niagara Falls to Tabua | 3,552.25 mi (5,716.79 km) |
| Niagara Falls to Tavira | 3,679.20 mi (5,921.10 km) |
| Niagara Falls to Tomar | 3,558.95 mi (5,727.58 km) |
| Niagara Falls to Tondela | 3,544.68 mi (5,704.60 km) |
| Niagara Falls to Torre de Moncorvo | 3,566.61 mi (5,739.90 km) |
| Niagara Falls to Torres Novas | 3,557.86 mi (5,725.82 km) |
