Northwood Headquarters Northwood Headquarters is a military headquarters facility of the British Armed Forces in Eastbury , Hertfordshire , England , adjacent to the London suburb of Northwood . It is home to three command and control functions of the British armed forces and North Atlantic Treaty Organisation ( NATO ) ; Permanent Joint Headquarters , Commander in Chief Fleet and the NATO Regional Command , Allied Maritime Component Command Northwood . History . The British armed forces first arrived on the site in 1939 , when Eastbury Park , Northwood , became the Headquarters of RAF Coastal Command . It was in fact the RAF who started going underground to build their Headquarters . In 1953 , the NATO Commander - in - Chief Eastern Atlantic Area , who was also Commander - in - Chief Fleet , established his Headquarters at Northwood . In April 1963 the Naval unit at Northwood was commissioned as HMS Warrior and in September 1971 the Royal Navy took over responsibility for the whole site . In 1978 the Flag Officer Submarines also moved his Headquarters to Northwood . As HQ of the Commander - in - Chief Fleet the site was the controlling Headquarters for Operation Corporate , the Falklands War . The site falls under the authority of Chief of Joint Operations following a handover from the Commander - in - Chief Fleet in 2002 . In 2006 major construction works commenced to improve the functionality of the site : the works , which involve the refurbishment or replacement of many of the key buildings for the Permanent Joint Headquarters , are being carried under a Private Finance Initiative contract by Carillion . The main entrance to the base is located on Watford Road , Northwood . Permanent Joint Headquarters . Permanent Joint Headquarters ( PJHQ ) is a tri - service organisation holding Operational Control of British armed forces joint military operation . PJHQ is headed by the Chief of Joint Operations . Single - service operations remain under the OPCON of the appropriate front - line command . Royal Navy . Northwood , as HMS Warrior , was the flagship of the Royal Navy ' s Commander in Chief Fleet from April 1963 , shortly after the transfer of the Home Fleet ashore in 1960 . Following the invasion of the Falkland Islands by Argentinian forces in 1982 , CINCFLEET was given command of the operation to recover the islands . The Operation was directed from Northwood with CINCFLEET staff augmented by personnel from corresponding UK Land Forces and RAF Strike Command headquarters . In 2002 , following a rationalisation , CINCFLEET moved the majority of the staff to Portsmouth , moving into HMS " Excellent " in 2004 . Commander Operations remains with the current operations staff on the Northwood site and CINCFLEET retains an office in addition to the Portsmouth location . Commander Operations is also commander of the corresponding NATO regional HQ . NATO and the EU . The NATO regional command , Allied Maritime Component Command Northwood , an element of Allied Joint Force Command Brunssum , is based in the site . Commander AMCCN is CINCFLEET Commander Operations . Previously AMCCN was designed Commander - in - Chief Eastern Atlantic ( CINCEASTLANT ) as part of Allied Command Atlantic . AMCCN provides the Northern Maritime command element of AJFCB to Allied Command Operations . A headquarters structure is available for the command of European Union military operation . Personnel to support this structure would be seconded from existing NATO and national posts in the site , augmented from elsewhere as required . Support units . The three Headquarters Staffs are supported by :