| Houston to Alenquer | 4,779.12 mi (7,691.25 km) |
| Houston to Alfena | 4,747.05 mi (7,639.63 km) |
| Houston to Alijo | 4,796.71 mi (7,719.56 km) |
| Houston to Aljustrel | 4,851.54 mi (7,807.81 km) |
| Houston to Almada | 4,781.67 mi (7,695.36 km) |
| Houston to Almargem | 4,771.69 mi (7,679.29 km) |
| Houston to Almeirim | 4,795.07 mi (7,716.92 km) |
| Houston to Amadora | 4,776.55 mi (7,687.11 km) |
| Houston to Amarante | 4,768.45 mi (7,674.08 km) |
| Houston to Amares | 4,746.70 mi (7,639.07 km) |
| Houston to Amora | 4,785.04 mi (7,700.78 km) |
| Houston to Anadia | 4,772.09 mi (7,679.94 km) |
| Houston to Angra do Heroismo | 3,854.45 mi (6,203.13 km) |
| Houston to Ansiao | 4,785.45 mi (7,701.44 km) |
| Houston to Anta | 4,748.08 mi (7,641.30 km) |
