Regional War Rooms and the Regional Seats of Government
Since the 1950s it has been assumed that under nuclear attack London would be completely destroyed and communications with the provinces would be severely disrupted.
Government of the nation from Whitehall would be untenable, so plans were laid for fourteen Regional administrative bunkers, each of which, in emergency, would have the absolute powers previously vested in Whitehall.
As the assumptions of nuclear war changed over the decades, so did nature of the bunkers required by the Regional Commissioners and their staffs. The Regional War Rooms of the early 1950s were replaced by the end of the decade by larger and harder Regional Seats of Government, which themselves were subject to a process of evolution that lasted until the early 1980s. The a completely new range of highly sophisticated bunkers - the RGHQs - were built that lasted until the end of the cold-war

Above, right and below: Regional War Room No.7, Brislington near Bristol

Built in 1954 this would have controlled south west England under atomic attack

Above and below, RGHQ No.7 at Chilmark near Salisbury. Opened in 1986, the bunker replaced the sub-regional controls at Hope Cove and Ullenwood