Aerial view of opposing trench lines between Loos and Hulluch, July 1917. German trenches at the right and bottom, British at the top-left.

The trench systems of 1915, 1916 and early 1917 became increasingly sophisticated as time, the lack of any significant advances or withdrawals and lengthy periods of inactivity allowed the soldiers abundant opportunities to improve the environment in which they lived and fought. Emplacements were routinely dug to depths of ten or twelve metres and included command and observation posts, bombardment shelters, sniper, machine-gun and sentry positions and suchlike, as well as field kitchens, medical aid posts and all manner of storage facilities (including often large quantities of ammunition and explosives). In early 1915 a typical basic dugout or shelter was constructed up to one metre wide (but no wider, in order to minimize the consequences of a direct hit by a shell), their sides reinforced with planks, and with a roof constructed of logs surmounted by three to four metres of earth, and finally a layer of earth mixed with straw.74 There were also chambers or rooms for resting, sleeping and eating, many of which were developed to remarkable levels of innovation and relative comfort behind the front-line trenches; such innovative and elaborate constructions often appeared in the second and third-line trench systems of quieter sectors too. In 1916 Victor Archard, a soldier of C Company, Heavy Branch of the British Machine-Gun Corps, and some of his comrades took the opportunity to investigate a recently captured German dugout ‘No 34A’ on the Western Front, where they found:

It was entered by between twenty-five and thirty stairs, boarded above and on the sides. The stairs gave place to a landing, then a sharp turn and an ascent of about nine steps. The first room contained a table, chairs, lamp, shelves and a large clock, while an exit led from the opposite wall. The room was papered and evidently well kept. From the middle of either side a passage led to a kitchen and store respectively, while the passages were of sufficient width to allow bunks with spring mattresses to be erected. On these beds were numerous expensive valises and new uniforms, also ammunition, tins of dubbin [waterproofing dressing for boots], boot polish etc. One bunk contained a dead German who had probably been killed there, or had crawled there to die. In the stores were several cases of lager beer and mineral waters, and a fair quantity of tinned meat of superior quality. There were also supplies of matches, some cigars and various articles of kit.

The same year, Lieutenant Carrol Whiteside of the 7th Battalion of the British army’s Border Regiment recorded his visit to a German brigade commander’s dugout in Fricourt Wood, when he observed that, ‘The place was sixty feet beneath the surface, down a steep flight of steps all boarded on the walls and roof and moreover distempered white. There were about eight fair-sized rooms, including an orderly room and servants’ rooms.’ On 29 November 1914, German gunner Herbert Sulzbach of the 2nd Battalion of the 77th Field Artillery Regiment, XIX Corps, wrote in his diary that, after a month occupying them, the dugouts of his battery in the area of Armentières had ‘tables and stoves and one even has a piano in it.’

While all sides engaged on the Western Front exhibited great ingenuity and skill in developing their defences, it is probably true to say that the German defensive positions of 1916 and 1917 achieved a greater degree of permanence and sophistication than those occupied by the Anglo-French troops. In part this reflected the general staff’s new commitment to a defensive strategy, with the German troops required primarily to hold the line in the west while their comrades on the Eastern Front dealt with the Russians. For the French and British governments however, nothing less than a capitulation and the removal of the German army from France and Belgium would do, which in turn meant that the French and British forces were necessarily committed to offensive action to break the stalemate.

As the two accounts above indicate, the German dugouts were regularly excavated deep underground, often accessed via stairways or ladders, all served by a network of interconnected communication trenches, pathways and tunnels. These routes gave ready access to the frontline defensive positions as well as providing a multiplicity of exits, escape routes, ventilation shafts and so on – making it possible for individuals and groups of men to move easily and quickly from position to position was one of the highest priorities. Many of these earthworks were set so far underground that even the heaviest shells could not affect them. There was a disadvantage to this, however, due to the time that it might take to get to the surface in case of an alarm, with as many as forty steps sometimes being the principal means of access to a relatively unsophisticated dugout, with the way into some others being described as the equivalent of ‘the stairs of a four-storeyed house’. Electric light illuminated most of these underground caverns, and telephone cables linked them with other positions in the line. Extensive revetting, concreting, floorboards, duckboards, ladders and stairways all added to the security and comfort of the thousands of men for whom the trenches had become their home. Barbed wire was laid to a width of 50 metres in front of the German trenches, and wooden knife-rest barriers (comprising a horizontal beam supported by a cross-piece at each end) laced with barbed wire were set across every approach route. Forward outposts and machine-guns covered every area from which an enemy patrol or larger-scale attack might approach, while along the front many hundreds of sentries were constantly on alert. This defensive shield led Ernst Jünger to describe everyday life in the trenches as ‘splendid days when, as a young officer, one could venture to sleep in pyjamas, and the automatic that lay to hand beside the ash-tray was only used when it was desired to break the monotony by going on patrol’, while, ‘one could traverse one’s whole front like a mole without once coming to the surface’.

Inevitably, the static nature and intermittent tempo of operations on the Western Front involved long periods of inactivity and monotony, but this in turn produced masterpieces of creativity as the soldiers constantly improved their living arrangements. Individual sleeping bays, wood-panelled walls, shelves, basic furniture, ‘pictures in colour from [the magazine] Jugend’, doors, curtains and suchlike were but a few of the more straightforward refinements that proliferated in the earthworks just behind the forward lines. So-called ‘trench art’ also became popular, with expended bullets and the brass cases of bullets and shells turned into matchbox covers, pens, cigarette lighters, ash trays, pipe cleaners and letter openers. During long hours spent in the trenches officers and soldiers also produced carved sets of chequers (draughts), dominoes and chess pieces, other board games, sketches and paintings, all sorts of carved wooden and metal souvenirs, models of military aircraft, guns and vehicles, as well as children’s toys. Meanwhile, hygiene, de-lousing and trying to keep body, clothing and equipment clean while in the trenches presented a constant battle – one frequently lost on a day-to-day basis, although units in the line usually managed to provide the soldiers with an opportunity to clean up, bathe, or at least have a proper wash with hot water somewhere to the rear of the front line every ten days or so.

At the same time the risks inherent in occupying such well-made dugouts set deep underground became very evident, as many of the obstacles erected in no-man’s-land when the lines were first established were gradually fragmented or destroyed by artillery and machine-gun fire, with little prospect of repairing or replacing them due to that same fire. In theory, no-man’s-land was an open space separating the two armies, but in many cases both lines of trenches were linked by communication trenches, saps (earthworks designed to undermine those of the enemy), tunnels and excavations dug in earlier times. In addition, where the lines might have moved a few hundred metres east or west, the residual earthworks that had originally been entirely within one side’s defences were sometimes left straddling no-man’s-land, with parts of that trench system now occupied by both sides. Virtually any of these dual-owned, old, redundant or disused trenches could provide routes by which a small number of attackers could infiltrate into the opposing side’s main trench system, and such considerations prompted the German army’s ‘front fighters’ on the Western Front to modify their tactics, weapons and equipment accordingly.

With the passage of time, both sides became technologically more innovative, as well as more aggressive and daring in their patrolling activities. As the tactics of trench warfare changed and the technology of death and destruction advanced, so the grenades of the trench raiders, the clouds of poison gas, the fire of flamethrowers, and the burning phosphorous of artillery shells and bombs took an ever greater toll of those troops who, while largely secure from artillery bombardment in their underground fortresses, were nevertheless unable to reach the surface in time to repel a surprise attack or trench raid, or to escape the noxious effects of gas or fire. Accordingly, the German high command eventually directed that forward trenches and dugouts were to be no deeper underground than two metres, thereby accepting the likelihood of greater casualties from artillery and mortar bombardment while reducing the risks of a surprise attack and of mass casualties underground caused by gas or flame. In recognition of the reduced level of protection such forward trenches would afford, they were provided with two-man ‘Siegfried shelters’ – semicircular holes dug into the side of the trench and extending some three metres, with a curved, corrugated iron roof supporting up to two metres of overhead protection. They gave the front-line troops some protection from artillery bombardment but virtually none from a direct hit and little if any from a shell landing within the trench close to the shelter.

Slightly forward of the main trench or built into its side were the observation, sentry and sniper positions, these often protected by steel plates into which loopholes had been set. The practice of occupying such positions well forward of the main trench line and accessed by a buried sap or tunnel was largely abandoned during the first year of the war because their isolation and vulnerability outweighed their ability to provide early warning of an attack. Even when they were located close to the main trench line, these positions were dangerously exposed. More often than not they lacked any sort of overhead cover apart maybe from a sheet of canvas or possibly a few pieces of wood to protect the occupants from some of the worst ravages of the sun in summer and the snow and rain in winter.

Although a post-winter thaw or heavy rainfall usually affected the forward positions more than those sited farther to the rear (i.e., in depth), inundations of the trenches were always thoroughly demoralizing. Carefully constructed and otherwise apparently sound earthworks were undermined and collapsed, dissolving into a mixture of mud, bits of timber and lumps of chalk or stone. At the same time, seemingly unstoppable rivers of mud and water flowed freely along walkways and into dugouts, stores and sleeping bays. These torrents frequently disinterred corpses hastily buried after earlier battles as well as uncovering the mouldering bodies of long-lost soldiers posted as missing in action weeks, months and even years before. Meanwhile, the countless shell holes and craters that pock-marked the battlefield rapidly filled with water, several of these often coalescing into great expanses of filthy, muddy water. Every one represented a potential death trap for any soldier or horse unlucky or careless enough to fall into its unfathomable depths.

Inevitably the years of trench warfare prompted many technological innovations, improved and new weapons, while tactical developments influenced specific events and tactical engagements to varying degrees. Probably no more than two of these new weapons truly had the potential to unlock the stalemate on the Western Front – poison gas, used by the German army in 1915, and tanks, deployed by the British from 1916. However, apart from facilitating some tactical successes, the army’s deployment of poison gas against Franco-Algerian and British troops in April and May 1915 simply heralded the arrival of an additional threat and new form of unpleasantness for those soldiering on the Western Front80 during the months and years that followed. The tank was a British invention, with its first appearance from 1916 and then in greater numbers in 1917 eventually making a major contribution to breaking the stalemate on the Western Front. The failure of the Germans to develop and exploit this particular weapon early enough meant that its battlefield success advantaged the Allies rather than the Germans and the other Central Powers.