| Middle River to Montalegre | 3,506.41 mi (5,643.02 km) |
| Middle River to Montemor-o-Novo | 3,570.18 mi (5,745.64 km) |
| Middle River to Montemor-o-Velho | 3,506.16 mi (5,642.62 km) |
| Middle River to Montijo | 3,535.47 mi (5,689.80 km) |
| Middle River to Mortagua | 3,521.06 mi (5,666.59 km) |
| Middle River to Moura | 3,622.64 mi (5,830.08 km) |
| Middle River to Murtosa | 3,493.79 mi (5,622.70 km) |
| Middle River to Nazare | 3,502.42 mi (5,636.60 km) |
| Middle River to Nelas | 3,537.47 mi (5,693.01 km) |
| Middle River to Obidos | 3,504.42 mi (5,639.81 km) |
| Middle River to Odemira | 3,579.53 mi (5,760.69 km) |
| Middle River to Odivelas | 3,518.70 mi (5,662.81 km) |
| Middle River to Oeiras | 3,514.85 mi (5,656.60 km) |
| Middle River to Olhao | 3,635.17 mi (5,850.25 km) |
| Middle River to Oliveira de Azemeis | 3,498.70 mi (5,630.61 km) |
