Work on the new Royal Ordnance factory at Wrexham began soon after the outbreak of war in 1939. Located where the Wrexham Industrial Estate is today, during the Second World War, Wrexham’s ROF facility made cordite, an explosive propellant for shells. ROF Bishopton, ROF Ranskill and ROF Sellafield being the three other propellant factories.
The site was chosen for its distance from European bombers while having good rail networks and a rural location that provided a good supply of labour but in a wide spread area.
The complex was spread over a large area to minimise any damage from aerial attacks. Any existing farm buildings were left in situ while the main buildings were camouflaged to deter reconnaissance.
The buildings were designed to resist incendiary bombs and blast, with thick walls, with no windows only small shuttered openings and reinforced roofs. These were then surrounded with earth banks both to deflect blast and to direct any explosion from within buildings upwards. Some were designed with weak end wall joints for this purpose. Many of the original buildings can still be seen today and still house smaller businesses on the estate, these can be told apart from the 1950's buildings by large grids near the roof, essential for ventilation of the buildings.
The Ministry of Works built a large water abstraction and treatment plant at Sesswick on the River Dee, just to supply the plant, which was amalgamated into the Wrexham Water Company (now Dee Valley Water) in 1951.To connect the site to the national rail network, a large marshalling yard of 10 separate roads, and these connected to the works internal network of rail lines. A passenger platform was built for military usage. All the cordite produced at the plant was taken by these sidings, along the Wrexham and Ellesmere Railway and then to Crewe. For shunting works, Diesels were used instead of Steam engines as they were less likely to ignite any stray cordite, however it is known the works had possession of an 1859 0-4-0ST known as Victory.
The site was well defended, both on the ground and from the air, and several Type 2 Pillboxes still remain in the area, found in areas untouched by modern industrial developments. The entire site was under a mile away from RAF Wrexham, which was home to at least one fighter squadron, for defending the regions industrial assets from bomber attack.
After the war, the need for cordite ceased, and so did the production facilities at Wrexham. Much of the buildings were left in place, abandoned, and agriculture again took over the fields surrounding the area. The combined closure of ROF Wrexham and the army returning caused much unemployment in the area, with major redundancies in the area's coal mines due to increasing motor travel. To mitigate this, a number of large factories and industrial estates were built in the area, including the Wrexham Industrial Estate on the site of the ROF.
History adopted from wikipedia