During the Cold War, the nature, intent, and scale of Soviet civil defense were the subject of heated debate in the West. Some analysts claimed that the USSR possessed a massive civil defense program capable of seriously destabilizing the strategic nuclear balance. This article draws on previously unexamined archival sources to investigate Soviet shelter construction from 1953, when the USSR's civil defense forces began planning for nuclear war, until the Cuban missile crisis in October 1962. These documents indicate that shelter construction consumed the majority of Soviet civil defense funding and was conducted by order of the Council of Ministers. Although the shelters were inadequate both technologically and quantitatively to protect the Soviet population from an all-out U.S. thermonuclear attack, they existed in significant numbers and represented a considerable expenditure of limited Soviet resources. These new revelations provide important insights into Soviet thinking about nuclear war during the Khrushchev era.