An Early Green Roof. With Houses.
During World War II there was some concern that the Japanese might attack the Lockheed Burbank Aircraft plant, so they decided to camouflage it- by turning it into a subdivision. It looks quite bucolic, with streets, cars and houses. ::Core77 calls it "largest trompe l'oeil ever made. It's Christo meets Carpaccio...meets G.I. Joe."