San Francisco International Airport
Air travel revolutionized San Francisco’s regional interaction without the same adverse economic effects of the railroad. Built in the 1920s, the San Francisco Airport (SFO) attracted both commercial and passenger flights. It eventually became the base for the first transoceanic air service, and was renamed the “San Francisco International Airport” in 1948 [27]. Now ranking seventh nationally in total passengers and 19th nationally in cargo, the airport is a major source of basic economic activity, bringing both people and goods through the region—much like the early sea trade did [27]. In 2012 alone, SFO produced an approximate economic impact of $55.8 billion for the metropolitan area via job creation, increased tourism, and increased industries to support the airport and visitors [6]. Airports with the highest rankings of passenger movement are often those that serve the largest regional areas, indicating metropolitan dominance of a particular place [15]. The airport positions San Francisco as a dominant metropolitan force—even if the airport is not located within the city.