| Llantwit Major to McKeesport (Pennsylvania) | 3,581.05 mi (5,763.15 km) |
| Llantwit Major to McKinleyville (California) | 5,126.52 mi (8,250.33 km) |
| Llantwit Major to McKinney (Texas) | 4,593.95 mi (7,393.25 km) |
| Llantwit Major to McLean (Virginia) | 3,534.12 mi (5,687.62 km) |
| Llantwit Major to McMinnville (Oregon) | 4,858.29 mi (7,818.66 km) |
| Llantwit Major to McMinnville (Tennessee) | 4,036.06 mi (6,495.40 km) |
| Llantwit Major to McNair (Virginia) | 3,542.75 mi (5,701.51 km) |
| Llantwit Major to McPherson (Kansas) | 4,372.89 mi (7,037.48 km) |
| Llantwit Major to Mead Valley (California) | 5,315.98 mi (8,555.25 km) |
| Llantwit Major to Meadow Woods (Florida) | 4,206.13 mi (6,769.12 km) |
| Llantwit Major to Meadowbrook (Virginia) | 3,613.27 mi (5,814.99 km) |
| Llantwit Major to Meadville (Pennsylvania) | 3,536.29 mi (5,691.10 km) |
| Llantwit Major to Mebane (North Carolina) | 3,749.43 mi (6,034.12 km) |
| Llantwit Major to Mechanicsville (Virginia) | 3,599.53 mi (5,792.89 km) |
| Llantwit Major to Medford (Massachusetts) | 3,134.99 mi (5,045.28 km) |
