I was doing some web browsing today and ran across this photo set on Flickr:
Modern military ruins of San Francisco
http://www.flickr.com/photos/telstar/sets/56935/
If you're into abandoned military bases, this set has some pretty fascinating stuff.
Modern military ruins of San Francisco
Interesting that the Presidio of San Francisco, former home of the Sixth Army wasn't in that collection. But that post and the surrounding area is mostly preserved for historical purposes by the US Park Service. About the only major structure that has been demolished is most of the Letterman Army Medical Center that served patients from WWII through Viet Nam. The new structure on that site is now the Letterman Digital Arts Center, home to Industrial Light & Magic and Lucas Arts. The last time I drove through the Presidio it looked like the exterior of most of the buildings had not changed at all from it's days as an open military base, though I understand that the interiors of the buildings had been renovated and brought up to building code standards; many are now leased to various organizations. The Post Cafeteria (that was public) had become a Burger King.