CABINET WAR ROOMS
Constructed within the basement of an existing public building, the Cabinet War Rooms were built just prior to World War II to enable continuity of Government in the event of a devastating aerial bombardment of London. The site was used extensively for both Cabinet and Defence Committee meetings throughout the war.
The Cabinet War Rooms were commissioned in 1938 as it became obvious that there would be another war with Germany. During World War I, English cities had suffered aerial attacks from Zeppelins and light bombers but the scale of the damage was relatively small. However, during the inter-war years aircraft had become larger and capable of carrying much heavier payloads. It was feared that in any future conflict, devastating air-raids would be mounted that could bring the country to a halt. To ensure continuity of Government, the Cabinet War Rooms were commissioned to serve as a hardened shelter equipped with all the facilities required for the War Cabinet and Chiefs of Staff. Work progressed quickly and the shelter became fully operational on 27 August 1939 - just one week before Britain declared war on Germany.
The new facility was a converted storage basement under the 'New Public Offices', a Government office building built between 1908 and 1917 originally to house the Office of Works and the Board of Trade (but from 1940 onwards used by Her Majesty's Treasury). The largest room of the basement facility was allocated for Cabinet meetings. Various other compartments included a map room, the Transatlantic telephone room, office space and accommodation. The site also included basic messing facilities although most staff would have continued to use above ground commercial outlets in the vicinity.
In the early months of the war little use was made of the new amenity but the start of the Blitz in September 1940 prompted increased use especially as No. 10 Downing Street was badly damaged by a bombing raid on 15 October 1940. During the six years of the war, 115 Cabinet meetings were held in the room as well as many sessions of the Defence Committee, which was also headed by Sir Winston Churchill. As both use of the facility increased and bombing of London intensified, the War Cabinet Rooms were made bomb-proof. This consisted of concrete reinforcement up to 1.5 metres thick (and which became known as 'the Slab'). In 1941 Churchill's wartime HQ was moved from Downing Street into the New Public Offices directly above the War Rooms. Concurrently, the facilities in the basement were extended to improve the domestic accommodation available to the Prime Minister, his wife and staff. This work was complete by late 1941 but, by this time, the worst of the bombing raids had passed and the private apartments were rarely used.
The final cabinet meeting was held within the war rooms on 28 March 1945 after which the V-bomb threat to London had ended. The facility was decommissioned on 16 August 1945. Almost immediately the site was recognised as an important historical asset and in 1974 it was handed over to the Imperial War Museum.
Johnson, B (2015). The Churchill Factor: How One Man Made History. Riverhead Books, London.
Holmes, R.T (2011). Churchill's Bunker: The Cabinet War Rooms and the Culture of Secrecy in Wartime London. London.
Kelly, J (2016). Never Surrender: Winston Churchill and Britain's Decision to fight Nazis Germany. Simon & Schuster, London.
Lukas, J (2001). Five Days in London, May 1940. Yale Nota Bene.
Moody, J (2009). From Churchill's War Rooms: Letters of a Secretary 1943-45. London.
Simkins, P (1984). Cabinet War Rooms. London.
The Cabinet War Rooms allows visitor access into the main compartments that formed the wartime complex. The attraction also includes the Winston Churchill museum.
New Public Offices. These Government buildings were constructed between 1908 and 1917 originally to house the Office of Works and the Board of Trade. From 1940 onwards the offices were used by Her Majesty's Treasury and in 1941 Churchill moved his wartime headquarters into the building.
Cabinet Room. The largest room was set aside for meetings of the Cabinet. Although the facilities in No. 10 Downing Street were used whenever possible, by the end of the war 115 Cabinet meetings had been held in this room.
Map Room. This was continuously manned throughout the war with the duty officers responsible for maintaining an up to date record of current military dispositions across the globe. They also prepared a daily brief for the King, Prime Minister and Chiefs of Staff.
Bombproofing. When the Cabinet War Rooms were commissioned in 1939 they had no bomb-proofing and the security of the site was simply reliant on it remaining secret. It remained this way throughout the Battle of Britain and it was only in December 1940 that bomb-proofing was added. This consisted of massive steel girders supporting a concrete slab - all of which was installed in utmost secrecy.
Transatlantic Telephone Room. During the war, telephone links between Britain and the USA were via a largely insecure radio-telephone link. In 1943 a scrambling device, known as Sigsaly, was installed.
Accommodation. Modifications to the facility in late 1940/early 1941 added accommodation for the Prime Minster and his wife. However, Churchill only slept in the Cabinet War Rooms on three occasions preferring to utilise a disused tube station at Down Street which had been converted into a comfortable bomb shelter.