| Castelo Branco to McKeesport (Pennsylvania) | 3,709.97 mi (5,970.62 km) |
| Castelo Branco to McKinleyville (California) | 5,582.14 mi (8,983.58 km) |
| Castelo Branco to McKinney (Texas) | 4,760.59 mi (7,661.43 km) |
| Castelo Branco to McLean (Virginia) | 3,622.22 mi (5,829.39 km) |
| Castelo Branco to McMinnville (Oregon) | 5,340.87 mi (8,595.31 km) |
| Castelo Branco to McMinnville (Tennessee) | 4,144.46 mi (6,669.86 km) |
| Castelo Branco to McNair (Virginia) | 3,632.60 mi (5,846.10 km) |
| Castelo Branco to McPherson (Kansas) | 4,607.41 mi (7,414.91 km) |
| Castelo Branco to Mead Valley (California) | 5,660.13 mi (9,109.09 km) |
| Castelo Branco to Meadow Woods (Florida) | 4,180.76 mi (6,728.29 km) |
| Castelo Branco to Meadowbrook (Virginia) | 3,680.51 mi (5,923.21 km) |
| Castelo Branco to Meadville (Pennsylvania) | 3,687.13 mi (5,933.87 km) |
| Castelo Branco to Mebane (North Carolina) | 3,811.14 mi (6,133.44 km) |
| Castelo Branco to Mechanicsville (Virginia) | 3,668.81 mi (5,904.38 km) |
| Castelo Branco to Medford (Massachusetts) | 3,236.54 mi (5,208.70 km) |
