| Round Rock to Montalegre | 4,844.44 mi (7,796.37 km) |
| Round Rock to Montemor-o-Novo | 4,913.32 mi (7,907.23 km) |
| Round Rock to Montemor-o-Velho | 4,847.82 mi (7,801.82 km) |
| Round Rock to Montijo | 4,878.77 mi (7,851.62 km) |
| Round Rock to Mortagua | 4,862.09 mi (7,824.78 km) |
| Round Rock to Moura | 4,965.96 mi (7,991.95 km) |
| Round Rock to Murtosa | 4,834.54 mi (7,780.44 km) |
| Round Rock to Nazare | 4,844.95 mi (7,797.19 km) |
| Round Rock to Nelas | 4,878.16 mi (7,850.64 km) |
| Round Rock to Obidos | 4,847.22 mi (7,800.85 km) |
| Round Rock to Odemira | 4,923.28 mi (7,923.26 km) |
| Round Rock to Odivelas | 4,861.99 mi (7,824.62 km) |
| Round Rock to Oeiras | 4,858.23 mi (7,818.57 km) |
| Round Rock to Olhao | 4,978.97 mi (8,012.88 km) |
| Round Rock to Oliveira de Azemeis | 4,839.18 mi (7,787.91 km) |
