After the bombing of Pearl Harbor during World War II, the possibility of enemy attack on the U.S. mainland became very real. Japanese submarines operated in offshore waters and shelled some shipping operations and oil installations off the coast of California and Oregon. To guard against potential invasion, the U.S. Army built the farm buildings here as an early warning radar station during 1942 to 1945. The cinderblock structures were disguised with shingled roofs, fake windows, and dormers so they would look like part of a working farm from the air, the sea, and even the road. Behind that camouflage, they housed dish-separation electronics equipment and two 50-caliber anti-aircraft machine guns. As part of a network of observation stations, soldiers and civilians stationed here reported suspicious boats and planes to a communications center in San Francisco, which was prepared to dispatch fighter planes if a craft was identified as hostile.