The Royal Navy Propellant Factory, Caerwent was a facility at Caerwent, Monmouthshire, Wales, UK, (later RAF Caerwent) which was originally dedicated to the manufacture and storage of Royal Naval munitions. Since its closure as an armament works in 1966, it has been used by the US military and the British Army. It is now used as the Caerwent Training Area. A new purpose-built military barracks is set to be built on the site to house 1st The Queen's Dragoon Guards and 1st Battalion, The Rifles from 2027. The large military site is situated north of the A48 road about west of Chepstow and east of Newport. The site, which is about by , encompasses a perimeter road that is more than long. The factory had its own standard gauge railway system, miles of roads and a wide range of buildings, from small earth-banked bomb stores to large four storey built brick buildings. Since 1993, the former factory site has been used for a variety of military and civil purposes, including military field exercises, car rallying, storage and breakdown of railway vehicles, nature preservation, and leisure activities such as Airsoft. Planning and construction In the summer of 1936 the Royal Navy drew up prequirements for a new factory were drawn up. The main priorities were: the establishment should not be vulnerable to air attack; should not be located in an industrial area, but sufficiently close to a populated area to provide an adequate workforce; should be close to a railway and to main roads; should be located on rough grassland with a gravel on sand subsoil with good natural drainage and a slope of about 1 in 30 to provide maximum safety in the highly dangerous nitroglycerine manufacturing and handling areas; the higher part should not have an elevation of not less than above the lowest part to limit the internal gradients. Like all explosive factories of this type, a capacious supply of water was required for use in the manufacturing processes. To manufacture 150 tons of cordite per week the factory would need 3 million imperial gallons (14,000 m³) of drinking quality water per day. In latter part of the 19th century, the Great Western Railway (GWR) had undertaken the engineering feat of constructing the Severn Tunnel under the River Severn. One of the major difficulties encountered underground was the 'Great Spring', which necessitated the pumping of over 9 million