Supporting these were to be thirteen simple forts, known as "Mobilisation Centres", which would contain the tools, stores and ammunition for the men of the Volunteer Force, who were tasked with digging the entrenchments and manning them against any invaders.[4] An earthen rampart with positions for light field artillery pieces and machine guns was surrounded by a ditch with a concrete revetment on the scarp face.[3] The growing superiority of the Royal Navy, and the signing of the Entente Cordiale with France, resulted in the reduced likelihood of an invasion and the London Defence Scheme was officially abandoned in March 1906.[5] In 1938, Fort Halstead became the home of the Projectile Development Establishment, which was continuing work on solid fuelled rockets that had started at Royal Arsenal in Woolwich two years earlier.[5] The work at Halstead resulted in the 7-inch Unrotated Projectile used on ships of the Royal Navy, and a 3-inch version that was operated by the British Army in hundreds of Z Batteries for the air defence of the United Kingdom.RARDE was home to a number of military simulation and war game projects, mainly aimed as assessing the effectiveness of future defence equipment procurement.Four years later, when DRA was itself merged to form the Defence Evaluation and Research Agency (DERA), the forensic explosives laboratory came under media and scientific scrutiny.
Fort Halstead former MOD establishment in Kent UK, viewed in 2011. At intervals there is a projection in the fence line, this is to allow those guards inside to get a better view along the outside of the fence.