| Serris to Marco de Canavezes | 751.13 mi (1,208.83 km) |
| Serris to Marinha Grande | 853.45 mi (1,373.50 km) |
| Serris to Massama | 918.94 mi (1,478.89 km) |
| Serris to Matosinhos | 770.29 mi (1,239.66 km) |
| Serris to Mealhada | 803.38 mi (1,292.91 km) |
| Serris to Melgaco | 708.30 mi (1,139.89 km) |
| Serris to Melres | 765.79 mi (1,232.42 km) |
| Serris to Mira | 810.28 mi (1,304.03 km) |
| Serris to Miranda do Corvo | 814.73 mi (1,311.19 km) |
| Serris to Mirandela | 702.50 mi (1,130.57 km) |
| Serris to Mogadouro | 695.37 mi (1,119.08 km) |
| Serris to Moimenta da Beira | 743.71 mi (1,196.88 km) |
| Serris to Moita | 915.59 mi (1,473.51 km) |
| Serris to Moncao | 718.18 mi (1,155.80 km) |
| Serris to Montalegre | 705.92 mi (1,136.07 km) |
