What it is: A full-fledged, constantly changing, outdoors and arts destination with a weekend's worth of things to do.
What it was: A military base until the Army decamped in 1994.
Why does the Presidio keep evolving?: By 2013, the park must be financially self-sufficient.
What's with all the bulldozers?: It's a five-year project to replace the Golden Gate Bridge approach with a greener, safer parkway.
Park acreage: Nearly 1,500
What $7,800 gets you: A month's rent in a new ultra-green three-story town-house near the park's southern edge.
What $100 gets you: A night at Rob Hill, the city's only campground--they're group sites, so invite 29 of your friends.
More shiny new things: The hilltop Lobos Valley Overlook with views of the Pacific. And a 22-room guesthouse--the park's first overnight lodging that's under construction.
The latest in landscape art: British artist Andy Goldsworthy returns with Wood Line, a sinuous shape that he's making with downed eucalyptus branches. Take the free PresidiGo Shuttle to stop 47 and walk up Lovers' Lane; www.presidio.gov/experiences