| Swindon to Mangualde | 808.75 mi (1,301.55 km) |
| Swindon to Marco de Canavezes | 777.89 mi (1,251.90 km) |
| Swindon to Marinha Grande | 885.07 mi (1,424.39 km) |
| Swindon to Massama | 955.79 mi (1,538.20 km) |
| Swindon to Matosinhos | 788.36 mi (1,268.74 km) |
| Swindon to Mealhada | 835.17 mi (1,344.07 km) |
| Swindon to Melgaco | 720.22 mi (1,159.08 km) |
| Swindon to Melres | 790.07 mi (1,271.49 km) |
| Swindon to Mira | 837.18 mi (1,347.30 km) |
| Swindon to Miranda do Corvo | 851.50 mi (1,370.36 km) |
| Swindon to Mirandela | 741.44 mi (1,193.23 km) |
| Swindon to Mogadouro | 744.22 mi (1,197.70 km) |
| Swindon to Moimenta da Beira | 781.70 mi (1,258.02 km) |
| Swindon to Moita | 957.53 mi (1,541.00 km) |
| Swindon to Moncao | 727.27 mi (1,170.43 km) |
