| Watford to Sesimbra | 1,005.16 mi (1,617.65 km) |
| Watford to Setubal | 995.84 mi (1,602.65 km) |
| Watford to Sever do Vouga | 844.26 mi (1,358.71 km) |
| Watford to Silves | 1,073.99 mi (1,728.42 km) |
| Watford to Sines | 1,031.98 mi (1,660.81 km) |
| Watford to Sintra | 988.44 mi (1,590.75 km) |
| Watford to Sobrado de Paiva | 823.21 mi (1,324.83 km) |
| Watford to Sobral de Monte Agraco | 969.56 mi (1,560.36 km) |
| Watford to Soure | 893.13 mi (1,437.36 km) |
| Watford to Tabua | 860.97 mi (1,385.59 km) |
| Watford to Tavira | 1,065.16 mi (1,714.21 km) |
| Watford to Tomar | 917.35 mi (1,476.34 km) |
| Watford to Tondela | 852.09 mi (1,371.31 km) |
| Watford to Torre de Moncorvo | 789.61 mi (1,270.75 km) |
| Watford to Torres Novas | 928.23 mi (1,493.84 km) |
