In1951, the Air Force built a radar station on top of Mt. Tam. It was part of a network of posts on both coasts that served as a warning system against a surprise air attack. The Mt. Tam radar station was linked to Hamilton Field, 10 miles away, where fighter jets could be mobilized in seconds – the Cold War was ever-present. For decades you could see them from across the bay — two giant white “golf balls” atop Mt. Tam. The white domes were the most visible part of the station. Made of nylon and rubber, and supported only by internal air pressure, they provided weather protection to the radar antenna. Inside the station, personnel monitored the radar’s 200-mile range on a large Plexiglas board. Although the threat subsided, the base stayed active until 1983. Years later, west of the domes, the base had deteriorated. Scattered over 100 acres, were 40 buildings with broken windows, a mess hall in ruins, a swimming pool full of dead leaves, cracked basketball courts, a tennis court, a ghostly movie theater, hobby shop, a sauna, and a row of small homes that once housed families. The buildings were finally demolished in 1996.