Paintings, not people, to be whisked to safety in nuclear holocaust plan from Britain
According to the 30-year-old files - described by historians as the "most secret" to be released by the National Archive at Kew to date - Russia had so many nuclear warheads trained on Britain that around 12 million citizens would have been wiped out.
People would have been urged to stay indoors while all radio and television were to be replaced by an emergency BBC broadcast telling them: "There is nothing to be gained by trying to get away".
While members of the public would not be offered a shelter in nuclear bunkers, the government had devised a strategy for saving the country's art treasures.
Masterpieces from galleries in Edinburgh and London would have been transported to Wales, where they would have been stashed in a slate quarry.
Meanwhile, the prime minister and top officials would have been taken to government bunkers manned by civil servants.
According to the 1975 Government War Book, much of which remains classified, a single, looped broadcast would have taken over the airwaves and television.