More than 40 million passengers fly in and out of Sky Harbor International Airport in Phoenix every year. City officials couldn't risk stifling this sizable economic engine during construction of a much-needed passenger train project.
To stay out of the way of planes, PHX Sky Train's guideway design takes it 90 ft over an active taxiway—billed by airport officials as a worldwide first—and then dips underneath two more taxiways before rising up to pass over a passenger concourse.