Work to convert the basement of the New Public Offices began, under the supervision of Ismay and Sir Leslie Hollis, in June 1938. [8] The work included installing communications and broadcasting equipment, soundproofing, ventilation and reinforcement. [9] Because the War Rooms are below the level of the River Thames, flood doors and pumps were installed to prevent flooding. [10] Meanwhile, by the summer of 1938 the War Office, Admiralty and Air Ministry had developed the concept of a Central War Room that would facilitate discussion and decision-making between the Chiefs of Staff of the armed forces. This is Ray’s recollection of that afternoon – as related in the letter by his wife Dorothy: “Churchill greeted Ray cordially, calling him by his first name… They talked about the similarity in their last names… about the United States… and particularly about old British coins and stamps. Ray mentioned he collected [them] and Churchill was very interested. Churchill offered Ray a cigar to smoke. Ray said he’d smoke it later, so Churchill gave him another one to smoke later. Ray was offered a drink of brandy, but refused because he was on duty. Churchill then continued to drink his brandy that was on a table beside his chair.

Most of these bunkers’ specific locations are lost to history, as the men who built them signed the Official Secrets Act, which prohibited them from talking about their assignments for decades. The best niche histories teach readers new information about oft-covered events, and this World War II account of Winston Churchill’s underground headquarters is an admirable example.

a b Hansard 6 December 1978; 'War Room, Storey’s Gate HC Deb 6 December 1978 vol 959 cc681-2W' Hansard 1803-2005. Accessed 18 March 2009. Deep under Whitehall lies a labyrinth of offices, map rooms and sleeping quarters whose very existence was kept a mortal secret from the Nazis. For this was where Churchill's war cabinet and military chiefs met to plan the strategy that was eventually to bring victory over Hitler in the Second World War. Restored today to exactly the condition they were left in at the end of the war in August 1945, the Cabinet War Rooms are a powerfully evocative time capsule. Military historian Richard Holmes has written a superb book that explains their central role in Britain's finest hour. The Rooms were opened to the public by Mrs Thatcher on 4 April 1984 in a ceremony attended by Churchill family members and former Cabinet War Rooms staff. At first the Rooms were administered by the museum on behalf of Department for the Environment; in 1989 responsibility was transferred to the Imperial War Museum. [35] [36]

On 26 September 1940, the rooms survived a near-miss when a bomb hit the Clive Steps almost directly above them, which prompted the authorities to construct a huge concrete slab to protect the cabinet room itself. Although at least 140 bombs had fallen on that area of Whitehall by the following February, the rooms escaped serious damage. Betty Green, a secretary working there at the time, reminisced: "I used to spend every other night sleeping in the office ... sometimes I was there for about three nights running because I just couldn't get home, so in some ways I was fortunate that one could get a good night's sleep because you didn't hear the bombs raining down, which is just as well, because we'd have all been buried alive in the Cabinet War Rooms." Waterfield, Giles 'The Churchill Museum: Ministry of sound' Museum Practice No.30 (Summer 2005) pp.18-21 Churchill stayed overnight down here at least five times in the winter of 1940, having been sneaked in at ground level and then, again, his presence hidden from most of the Down Street staff. While he slept on a modest camp bed, in the executive mess room, at least, he was able to live life well. The civil servant John Colville recalled in his diaries that at Down Street they were treated to caviar, Perrier-Jouet Champagne and 1865 brandy. Churchill's office-bedroom, open from 27 July 1940, [24] included BBC broadcasting equipment; Churchill made four wartime broadcasts from the Cabinet War Rooms, the first being on 11 September 1940. [25] Although the office room was also fitted out as a bedroom, Churchill rarely slept underground, [26] preferring to sleep at 10 Downing Street or the No.10 Annexe, a flat in the New Public Offices directly above the Cabinet War Rooms. [27] His daughter Mary Soames often slept in the bedroom allocated to Mrs Churchill. [28]Churchill’s war cabinet met in the bunker 115 times during the course of the war, discussing everything from Dunkirk to the Battle of Britain to Stalingrad. The staff kept the bunker operational 24 hours a day, seven days a week, until August 16, 1945, two days after Japan publically announced its unconditional surrender. Only then did the lights in the Map Room Annex—where all of the intelligence came in to Churchill’s military advisers—turn off for the first time in six years. Britain’s Prime Minister Winston Churchill sheltered here – in secret – in November and December 1940, when the German bombing campaign known as The Blitz was at its height, and a team of 40 staff worked here day and night on the war effort.