| Castelo Branco to Mauldin (South Carolina) | 4,003.98 mi (6,443.79 km) |
| Castelo Branco to Maumee (Ohio) | 3,854.33 mi (6,202.94 km) |
| Castelo Branco to Maumelle (Arkansas) | 4,493.95 mi (7,232.31 km) |
| Castelo Branco to Mayagüez (Puerto Rico) | 3,823.15 mi (6,152.77 km) |
| Castelo Branco to Mayfield Heights (Ohio) | 3,752.37 mi (6,038.86 km) |
| Castelo Branco to Mays Chapel (Maryland) | 3,581.75 mi (5,764.27 km) |
| Castelo Branco to Maywood (California) | 5,690.41 mi (9,157.84 km) |
| Castelo Branco to Maywood (Illinois) | 4,037.82 mi (6,498.25 km) |
| Castelo Branco to McAlester (Oklahoma) | 4,651.40 mi (7,485.71 km) |
| Castelo Branco to McAllen (Texas) | 5,119.71 mi (8,239.38 km) |
| Castelo Branco to McCalla (Alabama) | 4,289.33 mi (6,903.00 km) |
| Castelo Branco to McComb (Mississippi) | 4,535.21 mi (7,298.71 km) |
| Castelo Branco to McDonough (Georgia) | 4,141.71 mi (6,665.43 km) |
| Castelo Branco to McFarland (California) | 5,652.95 mi (9,097.55 km) |
| Castelo Branco to McHenry (Illinois) | 4,043.75 mi (6,507.78 km) |
