Mehrabad International Airport — Tehran, Iran

Long before Imam Khomeini International Airport took over as Iran's principal gateway in 2004, THR handled virtually every flight in and out of the capital. Opened in the late 1930s and expanded significantly during the mid-twentieth century, Mehrabad sits inside Tehran's western districts, close enough to downtown that its runways once defined the edge of the growing city. Today it functions primarily as a domestic hub, linking Tehran to provincial cities across Iran, while also hosting a limited number of international flights to nearby destinations and serving as a base for military and government aviation. Its central location keeps it far more convenient for many travelers than the newer airport built well outside the city. Generations of Iranians still associate THR with their first experience of air travel.