| Merthyr Tudful to Worthington (Ohio) | 3,715.79 mi (5,979.99 km) |
| Merthyr Tudful to Wright (Florida) | 4,323.91 mi (6,958.65 km) |
| Merthyr Tudful to Wyandanch (New York) | 3,295.19 mi (5,303.09 km) |
| Merthyr Tudful to Wyandotte (Michigan) | 3,626.38 mi (5,836.09 km) |
| Merthyr Tudful to Wylie (Texas) | 4,590.72 mi (7,388.04 km) |
| Merthyr Tudful to Wyndham (Virginia) | 3,605.00 mi (5,801.69 km) |
| Merthyr Tudful to Wyoming (Michigan) | 3,695.64 mi (5,947.55 km) |
| Merthyr Tudful to Wyomissing (Pennsylvania) | 3,420.21 mi (5,504.30 km) |
| Merthyr Tudful to Xenia (Ohio) | 3,771.26 mi (6,069.25 km) |
| Merthyr Tudful to Yakima (Washington) | 4,691.72 mi (7,550.60 km) |
| Merthyr Tudful to Yankton (South Dakota) | 4,133.39 mi (6,652.04 km) |
| Merthyr Tudful to Yauco (Puerto Rico) | 4,118.30 mi (6,627.76 km) |
| Merthyr Tudful to Yazoo City (Mississippi) | 4,357.11 mi (7,012.09 km) |
| Merthyr Tudful to Yeadon (Pennsylvania) | 3,408.16 mi (5,484.91 km) |
| Merthyr Tudful to Yelm (Washington) | 4,730.06 mi (7,612.29 km) |
