Air tram 3 was a 23rd century Federation air tram operated by Starfleet. It was attached to Starfleet Command on Earth.
In the mid-2270s, this air tram, with a female Human operator, transported civilians and Starfleet personnel, including Rear Admiral James T. Kirk, to the Starfleet Headquarters air tram station in San Francisco. (Star Trek: The Motion Picture)
In the original edit of the movie, this air tram approached the city from the north, alongside the bay side of the Golden Gate Bridge. This flight path was changed for the director's edition DVD release of the film. In this cut, the air tram approached the city from the north-west, flew over the bridge and through the two towers, and headed south towards the station.