RAF Eastcote, also known over time as RAF Lime Grove, HMS Pembroke V and Outstation Eastcote, was a UK Ministry of Defence site in Eastcote, within the London Borough of Hillingdon, northwest London. The British Government first used the site during the Second World War, constructing a military hospital in preparation for casualties from the D-Day landings. They were not required for the purpose and later became an outstation of the Bletchley Park codebreaking operations. During this time, Royal Air Force technicians and Navy Wrens supported the operations. The outstation closed soon after the end of the war, though became the first headquarters of Government Communications Headquarters (GCHQ), when the Bletchley Park codebreaking operations, including two Colossus computers, were moved th