Answer: Lockheed Martin Factories

After the 1941 attack on Pearl Harbor, the American military was deeply concerned that the Japanese military was planning to target critical military installations including the expansive production facilities of Lockheed Martin. In response to that concern, the Army contacted Col. John F. Ohmer and tasked him with outright concealing the Lockheed Martin facilities. Ohmer, impressed by the way the British had concealed their critical infrastructure during the Battle of Britain in 1940, had been campaigning for such urban camouflage tactics.

Ohmer recruited hundreds of set designers, painters, artists, from nearby Hollywood to help with the project. They set to work by unfurling thousands of yards of chicken wire, canvas, and netting to cover the factories in what appeared to be rolling hills. Three dimensional wire trees were erected, covered in leaves made from chicken feathers died green and brown to simulate actual foliage. Lightweight fake plywood homes were erected around parking lots painted green and brown to give the illusion of suburban lawns and sand lots dotting the landscape. Employees of Lockheed Martin would even go out on their lunch breaks and visit the fake homes, hanging fake laundry on the line and moving props around the yards to give the illusion of occupancy. Viewed from an aircraft the factories were completely indistinguishable from the surrounding countryside.