When it comes to vanished L.A. neighborhoods, my personal favorite is Berkeley Square, written of here in a number of posts by gsjansen, myself and others. Briefly, Berkeley Square was a private, gated street in the West Adams district approximately parallel to 22nd Street between Western and Gramercy. Successful downtown businessmen, lawyers, doctors, etc, commissioned top architects to build sizeable houses of all sorts of designs. Among the designers were Alfred Rosenheim, Myron Hunt, Elmer Grey, Robert Farquhar, Merl Lee Barker, Arthur B. Benton, and no less than the Greene brothers. It began in 1904, with a few original families remaining until the (very) bitter end ca. 1962, when, after at least a decade of decline, the 10 came through. As these photos reveal, the 10 itself really only took out the houses on north side of the street, although those along the south side went along for the ride into oblivion by being demolished for a school, all this destruction leaving behind only a possible bit of curbing toward the Gramercy end. Pictures of the street and the individual houses are hard to come by. There are a few aerial shots around, but now that I know about
historicaerials.com, thanks to Mr Downtown, we can have good side-by-side then-and-later comparisons of Berkeley Square, perhaps even more dramatic than the shots of Bunker Hill below. (I've chosen 1954 and 1972 for comparison because the images are the clearest.)

1954: Berkeley Square is the wide street at center

1954/1972

1972/1954

1972: I am actually amazed to see that the Lee Phillips house at #4 (right center below the ".COM") was still standing in 1972. Phillips was a Los Angeles lawyer who also built the house in Beverly Hills that became Pickfair. Subsequent owners included Haig Marquis Prince, an owner of downtown and Hollywood office buildings whose secretary once slapped him with a paternity suit. The last owner was Bishop "Sweet Daddy" Grace. The picture below is only the tip of an iceberg of amusements when it comes to the bishop--Sister Aimee was a shy nun compared to him. He's worth Googling.
http://farm3.static.flickr.com/2597/...d1d12e7bdd.jpg
Top four photos
historicaerials.com