| Llantwit Major to Security-Widefield (Colorado) | 4,613.54 mi (7,424.77 km) |
| Llantwit Major to Sedalia (Missouri) | 4,187.56 mi (6,739.23 km) |
| Llantwit Major to Sedro-Woolley (Washington) | 4,646.73 mi (7,478.19 km) |
| Llantwit Major to Seguin (Texas) | 4,830.55 mi (7,774.02 km) |
| Llantwit Major to Selden (New York) | 3,279.28 mi (5,277.49 km) |
| Llantwit Major to Selma (Alabama) | 4,245.16 mi (6,831.93 km) |
| Llantwit Major to Selma (California) | 5,238.60 mi (8,430.72 km) |
| Llantwit Major to Selma (Texas) | 4,844.42 mi (7,796.33 km) |
| Llantwit Major to Seminole (Florida) | 4,293.20 mi (6,909.23 km) |
| Llantwit Major to Seven Hills (Ohio) | 3,609.22 mi (5,808.47 km) |
| Llantwit Major to Seven Oaks (South Carolina) | 3,922.53 mi (6,312.70 km) |
| Llantwit Major to Severn (Maryland) | 3,505.05 mi (5,640.83 km) |
| Llantwit Major to Severna Park (Maryland) | 3,501.93 mi (5,635.82 km) |
| Llantwit Major to Sevierville (Tennessee) | 3,936.08 mi (6,334.51 km) |
| Llantwit Major to Seymour (Indiana) | 3,887.59 mi (6,256.47 km) |
