| South Portland to Montalegre | 3,097.47 mi (4,984.90 km) |
| South Portland to Montemor-o-Novo | 3,172.57 mi (5,105.75 km) |
| South Portland to Montemor-o-Velho | 3,103.72 mi (4,994.96 km) |
| South Portland to Montijo | 3,138.67 mi (5,051.21 km) |
| South Portland to Mortagua | 3,117.16 mi (5,016.59 km) |
| South Portland to Moura | 3,225.86 mi (5,191.52 km) |
| South Portland to Murtosa | 3,089.32 mi (4,971.79 km) |
| South Portland to Nazare | 3,102.47 mi (4,992.94 km) |
| South Portland to Nelas | 3,132.85 mi (5,041.84 km) |
| South Portland to Obidos | 3,105.46 mi (4,997.76 km) |
| South Portland to Odemira | 3,186.51 mi (5,128.18 km) |
| South Portland to Odivelas | 3,121.89 mi (5,024.19 km) |
| South Portland to Oeiras | 3,118.62 mi (5,018.93 km) |
| South Portland to Olhao | 3,243.08 mi (5,219.24 km) |
| South Portland to Oliveira de Azemeis | 3,093.70 mi (4,978.83 km) |
