| Llantwit Major to Mauldin (South Carolina) | 3,936.01 mi (6,334.39 km) |
| Llantwit Major to Maumee (Ohio) | 3,680.16 mi (5,922.65 km) |
| Llantwit Major to Maumelle (Arkansas) | 4,342.83 mi (6,989.10 km) |
| Llantwit Major to Mayagüez (Puerto Rico) | 4,113.49 mi (6,620.03 km) |
| Llantwit Major to Mayfield Heights (Ohio) | 3,594.39 mi (5,784.61 km) |
| Llantwit Major to Mays Chapel (Maryland) | 3,490.12 mi (5,616.81 km) |
| Llantwit Major to Maywood (California) | 5,337.46 mi (8,589.81 km) |
| Llantwit Major to Maywood (Illinois) | 3,830.21 mi (6,164.14 km) |
| Llantwit Major to McAlester (Oklahoma) | 4,472.08 mi (7,197.12 km) |
| Llantwit Major to McAllen (Texas) | 5,017.03 mi (8,074.13 km) |
| Llantwit Major to McCalla (Alabama) | 4,201.80 mi (6,762.14 km) |
| Llantwit Major to McComb (Mississippi) | 4,444.09 mi (7,152.07 km) |
| Llantwit Major to McDonough (Georgia) | 4,076.49 mi (6,560.48 km) |
| Llantwit Major to McFarland (California) | 5,276.96 mi (8,492.44 km) |
| Llantwit Major to McHenry (Illinois) | 3,826.76 mi (6,158.58 km) |
