San Francisco's position at almost the most extreme west point of the country has given it a lot of interesting distinctions in aviation history. Crissy Field,

San Francisco's position at almost the most extreme west point of the country has given it a lot of interesting distinctions in aviation history. Crissy Field, now a rather pleasant park just off the Presidio, was once an army airfield and the ending point of the first transcontinental flight completed in one day, dawn to dusk. There's a small plaque there commemorating the event. For many ears in the early 20th century it was a stopping point for air mail flights. A few of the buildings along there, now under NPS management, are old hangers from its previous use. Treasure Island also used to be a major seaplane airport, even after aviation use of the island itself ended (it had once been slated for the location of San Francisco International Airport, as a bit of trivia).