The Presidio was a famous military fort of Earth's history in the city of San Francisco. By the 24th century the Presidio was located on the grounds of Starfleet Academy. (ST - New Worlds, New Civilizations short story: "At Times of Peril")

By this time period, it also had an adjoining, sub-terranean cavern; complete with an archaeological excavation, from circa 1893. (TNG episode: "Time's Arrow")