| Gaithersburg to Arcos de Valdevez | 3,519.94 mi (5,664.80 km) |
| Gaithersburg to Arcozelo | 3,529.46 mi (5,680.12 km) |
| Gaithersburg to Arganil | 3,579.83 mi (5,761.17 km) |
| Gaithersburg to Arouca | 3,551.69 mi (5,715.90 km) |
| Gaithersburg to Arruda dos Vinhos | 3,563.50 mi (5,734.89 km) |
| Gaithersburg to Aveiro | 3,539.89 mi (5,696.91 km) |
| Gaithersburg to Aver-o-Mar | 3,514.31 mi (5,655.73 km) |
| Gaithersburg to Aves | 3,535.97 mi (5,690.60 km) |
| Gaithersburg to Azambuja | 3,571.09 mi (5,747.11 km) |
| Gaithersburg to Baiao | 3,555.86 mi (5,722.60 km) |
| Gaithersburg to Barcelos | 3,518.78 mi (5,662.93 km) |
| Gaithersburg to Barreiro | 3,572.16 mi (5,748.84 km) |
| Gaithersburg to Batalha | 3,558.59 mi (5,727.00 km) |
| Gaithersburg to Beja | 3,648.52 mi (5,871.72 km) |
| Gaithersburg to Belas | 3,559.04 mi (5,727.73 km) |
