Former World War I National Filling Factory, Barnbow


Heritage Category: Scheduled Monument

List Entry Number: 1415057

Date first listed: 26-Sep-2016

Location Description: Mainly focused in the valley of the Cock Beck, either side of Barnbow Lane, but with extensions southwards to the east and west of both Lazencroft Farm and Shippen House Farm.


Ordnance survey map of Former World War I National Filling Factory, Barnbow
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Location Description: Mainly focused in the valley of the Cock Beck, either side of Barnbow Lane, but with extensions southwards to the east and west of both Lazencroft Farm and Shippen House Farm.

The building or site itself may lie within the boundary of more than one authority.

District: Leeds (Metropolitan Authority)

Parish: Non Civil Parish

National Grid Reference: SE3873334711


Former First World War National Filling Factory surviving as standing, buried and earthwork remains.

Reasons for Designation

The former First World War National Filling Factory, Barnbow, is scheduled for the following principal reasons:

* Period: as the country’s first National Filling Factory, a milestone of the First World War and the country’s engagement in ‘Total War’ with the large scale employment of women in dangerous work; * Survival: the extensive buried and upstanding remains of the factory represents nearly its complete layout, Barnbow being the most complete surviving First World War filling factory nationally;

* Potential and Documentation: the archaeological remains, combined with extensive contemporary documentation, provides considerable potential for future research, public display and understanding;

* Social history: with its almost entirely female workforce, Barnbow played a significant role in the changing status of female workers and contributed to women winning the eventual right to vote;

* Commemoration: as the site of the country’s first major loss of female civilian lives during the First World War.


At the outbreak of the First World War, Britain had a very limited capacity for munitions production. Initially the government encouraged private enterprise to meet demand, but despite a near fourfold increase by March 1915, this was insufficient. The resulting ‘shell shortage’ crisis led to the formation of a coalition government and the creation of the Ministry of Munitions in May 1915. This new ministry, under David Lloyd George, promoted the construction of new munitions factories across the country. National Filling Factory (NFF) No.1 Barnbow was the first purpose-built filling factory to be built nationally for the filling of Quick-firing (QF) shells and cartridges with explosives (predominantly 13pdr, 18pdr and 4.5-inch, shrapnel and high explosive rounds, although larger calibre Breech-loading (BL) shells and cartridges were also produced in volume) and became the model for subsequent shell filling factories nationally. Its development was led by a board of Leeds industrialists established in August, with production starting in December 1915. Three months later, an additional plant was constructed at Barnbow for the filling of shells with Amatol (a high explosive formed by mixing ammonium nitrate with Trinitrotoluene or TNT). The rapid establishment of Barnbow and seven similar factories across the United Kingdom dramatically increased the production of munitions and allowed the launching of The Somme offensive in the summer of 1916. The workforce at Barnbow peaked at 16,000 in October 1916, 93% being women (the largest proportional percentage of any National Filling Factory), a third of whom came from Leeds, the rest travelling from across the region from as far away as York, Harrogate and Selby, most travelling in by rail. The organisation of the factory staff was based on the novel principle of ‘dilution’, reducing the task undertaken by a single skilled worker into a series of simple tasks that could be performed repetitively by semi-skilled workers.

To reduce the risk of explosions, different stages were carried out in different buildings, with the quantity of explosives in a building at any one time being limited. The buildings themselves were of light-weight timber-framed construction, those in the ‘danger areas’ designed to be ‘frangible’, that is to blow apart easily rather than concentrating the effects of blast in an accident. The factory was served by an internal railway system with 13 miles of standard gauge lines connected to the national rail network. Materials were moved between, and sometimes through buildings, using horse-drawn tramways, the factory having a 10 mile network of 2-ft (0.61m) gauge 'Jubilee Track'. In 1916, 150 railway truck-loads of munitions were leaving the factory every day. By autumn 1918 this had risen to 600 loads a day, around 10,000 tons of munitions per week produced by a highly efficient, nearly entirely female, workforce of 9,000. By the end of the war, Barnbow had dispatched 566,000 tons of ammunition including 24,750.000 shells and 36,150,000 breech-loading cartridges of all sizes.

Regrettably, there were a number of accidents at the factory and explosions occurred on three separate occasions. The most serious incident occurred on the 5th December 1916, when 35 women were killed by a blast in one of the shell fusing rooms - Building 42, just on the E side of Barnbow Lane, a little to the N of Cock Beck. Although the explosion was heard for miles around, the deaths of the women and the treatment of the injured was not reported in the press. This incident was the first occasion that a large number of civilian women workers were killed while undertaking war work and it was feared that an announcement would have had a detrimental effect on morale and recruitment into the factories, and even after the war, the incident received little official recognition. Two further women were killed on 21st March 1917, and three men lost their lives in a blast in one of the incorporating rooms of the Amatol plant on 31st March 1918. A detailed plan of the factory survives: this allows the layout of surviving earthworks and building remains to be clearly understood, enabling an appreciation of the way that the factory operated. Explosives (mainly cordite, and powdered TNT) were brought in by rail and stored in expense magazines sited in the NW part of the site until needed. Shell cases and other materials were brought into the eastern side of the factory to the Empty Shell Store which was sited at the former NE corner of the site, and the North and South Stores, situated to the north of Cock Beck, adjacent to the filling rooms. Although not listed on the archive map of the site, empty shells arriving on site were usually de-scaled and painted in rooms associated with the Shell Store. The factory produced all of its own timber packing cases, the Box Factory being on the E side of Barnbow Lane, just S of the Cock Beck. Workers arrived at a dedicated station – Barnbow Halt on the main line railway situated to the S of the factory. All individuals passed through a booking office supervised by a guardroom, before entering the main entrance and waiting rooms, then carrying on through the Women’s Canteen complex to the Shifting Rooms, where they changed into their magazine clothing (designed to prevent sparks) before proceeding onto the filling sheds via ‘cleanways’; raised timber walkways. The filling sheds were arranged in long E-W blocks either side of Barnbow Lane, both N and S of the beck in the northern side of the site. Once filled and packed, the munitions were stored in magazines operated by the Army Ordnance Department in the SW side of the site adjacent to Manston Lane; the factory and the stores protected from blast in either direction by the rising ground immediately to the NE of Lazencroft Farm which lies outside the area of the scheduling. From 1917, additional magazines were built 0.5km to the W (outside the area of assessment and no longer extant). Because of breaking convention by employing a largely female workforce, particular attention was given to welfare facilities. The offices, canteens, general stores, and the shifting rooms were situated centrally, in the ‘safe’ area, with the women’s canteen and shifting rooms to the W of Barnbow Lane and the less extensive men’s facilities to the E. The factory had its own dairy herd of 120 cows housed at Shippen House Farm to supply workers with milk, as this had been found to reduce the yellowing effect on skin caused by handling certain explosives. Vacant land was also cultivated to provide fresh produce for the canteens. The Amatol plant was a self-contained complex sited to the E of Shippen House Farm with its own offices, canteens, and shifting rooms, set within a railway loop that served a TNT store, a TNT melting house, an Ammonium Nitrate preparation house, an empty shell store, a bulk store, and a filled shell store. The plan-form of the new factory showed an improved and efficient flow of materials throughout the filling process.

After the end of the war, the factory became Depot No. 85 Leeds as part of the Central Stores Department, and was used for the de-commissioning of small arms ammunition and the storage and disposal of substantial volumes of surplus war materials. By 1924, the filling factory buildings had been largely demolished, with the land returned to the Gascoigne estate, which developed the site of the Amatol factory as a colliery; claimed as the world’s first to be entirely operated by electricity. The colliery closed in 1930. During the Second World War and for a time subsequently, Barnbow was used as a food store.


PRINCIPAL ELEMENTS: First World War munitions factory surviving as a series of building foundations, earthworks, and demolished and buried remains. GENERAL LAYOUT: the original factory is focused on the shallow valley of the Cock Beck which was followed by a standard gauge railway which looped to the S. Spread across the western part of this area were the expense magazines. To the centre, just W of Barnbow Lane, were the North and South Stores which flanked the railway. To the N and S of these stores were the filling sheds, with further filling sheds on the E side of the lane, N of the beck. A set of boiler houses lay to the E with the Box Factory to the S and the Shell Store to the N (for receiving shell cases for filling). On the higher ground to the S, mainly on the W side of the Barnbow Lane, was the ‘safe’ area including the Shifting Rooms, Offices and Women’s Canteen, the Men’s Canteen being on the E side of the lane. Served by the southern side of the railway loop, between Lazencroft and the N-S Barnbow Lane, were 8 magazines for completed munitions awaiting shipping. The Amatol Plant lay to the E of Shippen House and was contained within a smaller railway loop extending E of the main railway loop. DESCRIPTION: the most substantial set of in situ remains are the building platforms for the various buildings in the safe area centred around 175m NW of Shippen House. These are of brick, concrete and earthworks, standing up to 1m high. To the N, the footings and earthworks of the filling sheds also survive as upstanding features, but appear more disturbed by demolition. However smaller features, such as stanchions which supported the raised timber cleanways can also be identified. Other remains, such as those related to the horse-drawn tramway system, will survive as buried remains. The earthworks, concrete footings, and partial structural remains are generally well defined either as raised or sunken rectangular platforms, with a mixture of concrete floors and earth platforms hidden beneath accumulated plant material. The concrete floors of some of the structures have been broken up and left in situ, this particularly being the case with the North and South Stores. The site of Hut 42, the scene of the December 1916 accident is thought to lie approximately 50m NW of the bridge carrying Barnbow Lane across the Cock Beck. This bridge is an C18 arched masonry bridge that was modified and widened for the construction of the munitions factory.

The NE part of the complex, including the site of the Shell Store, one set of filling sheds (Block Y) and about seven other buildings, has been completely cleared and returned to agriculture and consequently is not included within the scheduling. To the S, included within the scheduling, the Cock Beck is culverted for about 40m with a surviving brick and concrete structure that originally supported boiler houses and two railway lines. Upstream to the W, there are two surviving concrete weirs which were designed to provide water for the factory’s fire brigade. On the rising land to the S, the footprint of the Box Factory survives as a clear earthwork depression, whilst to the SW, on the E side of Barnbow Lane, the Men’s Canteen and Block L (thought to be low risk filling sheds) survive as low upstanding platforms. Two further blocks (Block M and N) to the S of an E-W trackway no longer appear to survive and thus their area has not been included in the scheduling. The two standing buildings within the area of the scheduling, within the same field as the Box Factory, are both later: the crow-stepped gabled building to the SE is a former electrical substation built for the 1920s colliery; the flat roofed building to the NW is a guard house built for the 1940s food store.

The NW part of the monument includes the footings of 15 rectangular-plan expense magazines that are widely separated from each other and survive as very low earthworks and buried remains. More substantial are the eight magazines regularly spaced along the course of the S side of the railway loop, N of Manston Lane. These appear as raised rectangular earthwork platforms designed to allow direct loading onto standard gauge railway waggons. The scheduling also includes the course of the railway lines where the track beds can still be clearly traced as earthworks (either as embankments cuttings or traverses). This includes the embankments of the turning wye to the N of Lazencroft Cottage, and the loop around the Amatol plant to the E. Most of the buildings of the Amatol plant have been cleared leaving little trace, and their sites have thus not been included within the scheduling. However on the W side of the plant, N of Shippen Cottages, the substantial brick and concrete building platform for the Melting House does survive, reused as the floor of a modern agricultural building. This platform is included in the scheduling, although the modern agricultural buildings are excluded. EXTENT OF SCHEDULING: includes all parts of the site that retain significant earthworks or upstanding features of the former First World War, National Filling Factory No. 1 Barnbow. The boundaries of the monument are mainly drawn to modern boundaries, these generally following those depicted on a map of the factory dated 1924. However the area has been reduced to remove the area to the NE that has been returned to arable agriculture, most of the area of the Amatol plant that has also been cleared to form playing fields, and the land to the W, N and E of Shippen House which also no longer retains earthwork remains. The land to the immediate S of Manston Lane does retain some earthwork and structural remains, but these do not clearly relate to features shown on the 1924 plan and are considered to be largely the product of the 1920s colliery. Further to the S, close to the railway, are the footings and earthworks of Barnbow Halt, the booking office, and a guard room: however these peripheral features are not included in the scheduling. The SE part of the monument, covering the surviving structural and earthwork remains of the Amatol plant and its railway loop, is not drawn to modern boundaries because this would be too extensive. Instead, the scheduled area is drawn to include the upstanding remains with an additional 2m margin. To the SW, the scheduling is extended to include the turning wye and the western part of the railway loop, even though these lay outside the boundary of the factory mapped in 1924. This area also includes a siding and the site of a TNT magazine. The monument encircles, but does not include, Lazencroft Farm and the low hill to its N.

EXCLUSIONS: the chain link fence to the E of Barnbow Lane, and N of the western portion of Shippen Plantation, all fence posts, gate posts, telegraph poles, sign posts, water troughs, the three Turner's Curved asbestos huts situated to the NW of the Amaranth Cricket and Football Club playing fields, and the modern farm buildings built on the platform of the former TNT melting house are all excluded from the scheduling; however, the ground beneath is included.


Books and journals
Anon, , History of the Ministry of Munitions, Vol X, The Supply of Munitions, Part V, Gun Ammunition: Filling and Completing, (1921), 15 - 43
Cocroft, W, Dangerous Energy The Archaeology of Gunpowder and Military Explosives Manufacture, (2000), 176 - 178
Gummer, R.H. (Author), The Story of Barnbow, (1919)
Barnbow Factory Memorial Cross Gates, accessed 4th March 2016 from
Barnbow lasses worksheets, accessed 4th March 2016 from Shells, shells and more shells.pdf
Barnbow Lasses, Ben Johnson, accessed 4th March 2016 from
Barnbow Munitions Factory 1915-1918, Roll of Honour - The Women Who Died, Darren Wortley 2009, accessed 4th March 2016 from
Barnbow: Cross Gates factory horror that stayed a secret, accessed 4th March 2016 from
Leodis: a photographic archive of Leeds, accessed 4th March 2016 from
The Story of Barnbow Pit (1924-1930), Part 1 The Early Years, and Part 2 The Disaster, accessed 26th April 2016 from
York Munitions Workers Memorial, accessed 4th March 2016 from
A Brief History of Barnbow Munitions Factory - National Filling Factory Barnbow Depot No.85 Leeds, G.R. Douglas Laycock
History and Record of Barnbow National Filling Factory (MSS), R.H. Gummer, 20th Sept 1919
Research Report series no. 76-2015, First World War National Factories: an archaeological, architectural and historical review, David Kenyon, 2015
West Yorkshire Archaeology Advisory Service: Walkover Survey - Barnbow National Filling Factory No 1

End of official listing