| On Top of the World Designated Place to Mangualde | 4,174.94 mi (6,718.92 km) |
| On Top of the World Designated Place to Marco de Canavezes | 4,145.42 mi (6,671.41 km) |
| On Top of the World Designated Place to Marinha Grande | 4,129.69 mi (6,646.10 km) |
| On Top of the World Designated Place to Massama | 4,129.22 mi (6,645.34 km) |
| On Top of the World Designated Place to Matosinhos | 4,117.65 mi (6,626.71 km) |
| On Top of the World Designated Place to Mealhada | 4,143.66 mi (6,668.58 km) |
| On Top of the World Designated Place to Melgaco | 4,124.34 mi (6,637.48 km) |
| On Top of the World Designated Place to Melres | 4,134.73 mi (6,654.20 km) |
| On Top of the World Designated Place to Mira | 4,128.36 mi (6,643.96 km) |
| On Top of the World Designated Place to Miranda do Corvo | 4,154.47 mi (6,685.98 km) |
| On Top of the World Designated Place to Mirandela | 4,189.04 mi (6,741.60 km) |
| On Top of the World Designated Place to Mogadouro | 4,215.00 mi (6,783.38 km) |
| On Top of the World Designated Place to Moimenta da Beira | 4,175.95 mi (6,720.54 km) |
| On Top of the World Designated Place to Moita | 4,146.30 mi (6,672.83 km) |
| On Top of the World Designated Place to Moncao | 4,114.39 mi (6,621.46 km) |
