Presidio
From Memory Alpha, the free Star Trek reference
The Presidio is the site of an ancient military post adjacent to the city of San Francisco on Earth.
Starfleet Command Headquarters and Starfleet Academy eventually occupied the Presidio, as well as grounds north of the Golden Gate at Horseshoe Bay. Mindful of the site's history, Starfleet maintained the ancient coastal defense installation "Fort Point", as well as the iconic Golden Gate Bridge (completed in 1937) until its catastrophic damage in the Breen raid of 2375. (Star Trek: The Motion Picture; DS9: "The Changing Face of Evil"; VOY: "Endgame")
There was once a mine shaft located on the grounds of the Presidio within which there was an entrance to an underground cavern where Data was decapitated. (TNG: "Time's Arrow, Part II")
[edit] Background
The Presidio was founded as the northernmost outpost of the Spanish Empire in 1776, and later occupied by Mexico and the United States of America. It was key to the defense of San Francisco Bay and the North American west coast until its obsolescence in the late 20th century.
The shore battery "Fort Point" (completed in 1861) is visible as the small brick structure at the base of the Golden Gate Bridge in a scene from Star Trek: The Motion Picture, as Admiral Kirk's travel air tram approaches the air tram station at the Presidio.
