173rd Tunnelling Company
The 173rd Tunnelling Company was a Royal Engineers unit that conducted offensive and defensive underground warfare on the Western Front during the First World War.
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Overview
The 173rd Tunnelling Company was a specialist unit of the British Army's Corps of Royal Engineers, formed in March 1915 during the First World War. It belonged to the group of tunnelling companies created after the British Expeditionary Force recognized that German forces were organizing systematic underground mining beneath the trench lines. The companies were established to conduct mine warfare, counter-mining, and a wider range of underground engineering tasks in the confined and dangerous environment of the Western Front. The unit's work included driving galleries beneath no man's land, placing and maintaining explosive mines under enemy positions, listening for hostile digging, and constructing subterranean facilities. These facilities included troop accommodation, communication subways, saps, cable trenches, signal chambers, medical spaces, and deep dugouts intended to protect headquarters and troops from artillery fire. Personnel were drawn principally from the Royal Engineers and were supplemented by infantrymen when operational requirements demanded it. Like other early tunnelling companies, the 173rd benefited from the recruitment of experienced coal miners and other men accustomed to underground work. The company served under Second Army in the Ypres Salient for much of its existence, although it was also deployed to sectors near Laventie, Aubers Ridge, Cuinchy, Loos, Hulluch, and the Somme. Its best-known early operation took place at Hill 60 near Ypres. Beginning in March 1915, the company drove a series of tunnels toward the German positions and prepared six mines. On 17 April 1915, at 19:05, the mine group was fired. This was the first occasion on which a Royal Engineer tunnelling company detonated mines beneath enemy lines, making the operation an important early demonstration of organized British underground warfare. The unit subsequently supported preparations for the Battle of Aubers Ridge in May 1915, undertook counter-mining near Cuinchy, and from early 1916 to April 1917 worked through several underground levels in the Hill 70, Copse, and Double Crassier area near Loos. Some experienced personnel were transferred or attached to newly formed tunnelling companies as the British underground-warfare organization expanded. In 1917 the company returned to the Ypres area and helped construct deep dugouts around Yorkshire Trench and the Ypres Canal. These structures formed part of a wider defensive and command system intended to support the forthcoming Passchendaele offensive. Yorkshire Trench and several nearby dugouts served as headquarters for formations including battalions of the Royal Welch Fusiliers. The work was particularly hazardous because the excavations had to be made quietly, at shallow distance from German positions, and in unstable ground. During the German Spring Offensive of 1918, the 173rd Tunnelling Company was employed near Wiencourt on the Somme. Its personnel helped delay the German advance, including work associated with the destruction of bridges. On 25 March 1918, members of the unit were temporarily reorganized as infantry in No. 2 Royal Engineers Battalion for emergency defensive duties. After the German breakthrough in the Lys sector, the company helped construct and wire a defensive line extending from Reningelst toward Saint-Omer. Following the Armistice of 11 November 1918, Captain D. Richards MC became the last officer of a Royal Engineers tunnelling company to leave French soil. The 173rd Tunnelling Company was a wartime formation rather than a commercial brand, and it has no continuing consumer products or commercial operations. Its historical significance lies in its contribution to the development of British military mining, counter-mining, underground protection, and battlefield engineering.
History
The 173rd Tunnelling Company emerged from the British Army's rapid response to German underground warfare on the Western Front. By January 1915, the British Expeditionary Force had recognized that German mining was being carried out according to an organized system, while British forces lacked both appropriate counter-tactics and specialized underground listening equipment. Engineer-in-Chief Brigadier George Fowke consulted the mining specialist John Norton-Griffiths, and the War Office formally approved the tunnelling-company scheme on 19 February 1915. Companies numbered 170 through 177 were prepared for deployment during February, with the 173rd formed in March. The first companies were Royal Engineers formations normally consisting of five officers and 269 sappers, with additional infantrymen attached when necessary. Because experienced underground workers were scarce, the army recruited coal miners and other men with relevant mining skills, sometimes outside normal recruiting arrangements. The early companies were sent to the Ypres Salient, where underground fighting intensified around Hooge, Hill 60, Railway Wood, Sanctuary Wood, St Eloi, and The Bluff. From its formation until the end of the war, the 173rd served primarily under Second Army in the Ypres Salient, initially moving into the Fauquissart area near Laventie. Its first major operation was at Hill 60. British and German forces had already carried out small-scale mining in the area, but the arrival of specialist tunnellers made possible a much larger and more systematic attack. Starting in early March 1915, the company dug a shaft and several galleries toward the German line. The miners encountered human remains underground and had to use quicklime during the work. By completion, the tunnels extended more than 100 yards toward the enemy positions. Six mines were prepared: two northern mines carried charges of approximately 2,000 pounds each, two central mines carried approximately 2,700 pounds each, and a southern mine was packed with about 500 pounds of guncotton before work on it was halted near a German tunnel. The charges were ready on 15 April and were fired at 19:05 on 17 April. The event marked the first mine firing beneath enemy lines by a Royal Engineers tunnelling company. The company then participated in underground preparations for the Battle of Aubers Ridge on 9 May 1915, working under I Corps and the Indian Corps. The operation formed part of the Second Battle of Artois and represented only the second British use of specialist tunnelling companies. The 173rd later extended its work toward Rue du Bois and Red Lamp. During the summer it operated near Cuinchy under the 2nd Division, alongside other Royal Engineers tunnelling companies. In January 1916, the unit moved to the Hulluch-Loos area. It sank shafts and drove galleries to counter German mining activity south and east of Loos. When the 255th Tunnelling Company was formed that month, experienced officers and men from the 173rd were attached to the new formation. From January 1916 until April 1917, the 173rd fought an underground campaign in the Hill 70, Copse, and Double Crassier sector on three levels commonly identified as Main, Deep, and Deep Deep. The 258th Tunnelling Company supported this work after its arrival in April 1916, and the sector was later taken over by the 3rd Australian Tunnelling Company. In spring 1917 the 173rd moved to the Ypres Canal sector near Boezinge. There it helped construct the deep dugout associated with Yorkshire Trench and several other underground headquarters. Yorkshire Trench was a first-line trench for roughly a year before the Passchendaele fighting, and its completed dugout later accommodated headquarters for the 13th and 16th Battalions of the Royal Welch Fusiliers. Other nearby sites, including Butt 18, Nile Trench, Heading Lane Dugout, Bridge 6, and Lancashire Farm Dugout, provided battalion and brigade headquarters. Deep-dugout construction was exceptionally difficult because the ground was unstable and the work had to remain concealed from German observers only a few hundred metres away. The German Spring Offensive changed the company's role from specialized mining to emergency battlefield engineering. In March 1918 the unit was working with the 177th Tunnelling Company on the Fifth Army's Green Line near Wiencourt. When the offensive began on 21 March, the tunnellers helped stop or slow the retreat of Allied units on the Guillaucourt-Marcelcave road. They also contributed to the destruction of Somme bridges to impede the German advance. On 25 March personnel were converted temporarily into infantry as No. 2 Royal Engineers Battalion. In April, after German forces broke through the Lys positions, the company left its camp near Boeschepe and joined other tunnelling companies in digging and wiring a defensive line from Reningelst toward Saint-Omer. After the Armistice on 11 November 1918, Captain D. Richards MC was the last officer of a Royal Engineers tunnelling company to leave France. The 173rd Tunnelling Company therefore belongs to the wartime history of the Royal Engineers rather than to an ongoing commercial organization. Its surviving legacy is represented by military histories, battlefield archaeology, and preserved underground sites such as Yorkshire Trench.
- 1918
Emergency infantry and defensive duties
[1]During the German Spring Offensive, company personnel helped destroy bridges, served temporarily as infantry, and built defensive lines in Flanders.
- 1918
Armistice and departure from France
[1]After the Armistice, Captain D. Richards MC became the last officer of a Royal Engineers tunnelling company to leave French soil.
- 1917
Ypres deep-dugout work
[1]The company worked on Yorkshire Trench and other protected headquarters in the Ypres Canal sector.
- 1916
Loos counter-mining campaign begins
[1]The unit moved to Hulluch-Loos and began sustained counter-mining across multiple underground levels.
- 1915
Tunnelling-company scheme approved
[1]The War Office approved the creation of specialist British tunnelling companies after investigations into German mining on the Western Front.
- 1915
173rd Tunnelling Company formed
[1]The company was established as a Royal Engineers tunnelling formation during the expansion of British underground-warfare capabilities.
- 1915
Hill 60 mines fired
[1]On 17 April at 19:05, the company fired six mines prepared beneath German positions at Hill 60 near Ypres.
- 1915
Aubers Ridge preparations
[1]The company supported underground operations before the Battle of Aubers Ridge and later extended work toward Rue du Bois and Red Lamp.
Products and positioning
A specialist First World War military engineering unit focused on underground warfare, battlefield mining, counter-mining, and protected subterranean infrastructure.
Military engineering · 1915
Offensive mine warfare
The company's principal offensive capability was the excavation of galleries beneath enemy trenches and the placement of large explosive charges. Its Hill 60 operation demonstrated how specialist tunnellers could create a coordinated underground attack in support of surface operations.
Military engineering · 1915
Counter-mining
The unit located, monitored, and opposed German underground activity by sinking shafts, driving galleries, and working through multiple levels. Its Loos and Hulluch operations were intended to protect British positions and deny the enemy control of the subterranean battlefront.
Fortification · 1917
Deep dugouts and underground headquarters
The company built protected underground accommodation and command facilities, particularly in the Ypres Canal sector. Yorkshire Trench and nearby dugouts provided shelter and headquarters space for battalion and brigade formations during the Passchendaele period.
Military engineering · 1918
Field defensive engineering
In 1918 the company's role broadened to emergency surface defense. Its personnel helped demolish bridges, dig trenches, erect wire obstacles, and construct a defensive line between Reningelst and Saint-Omer after German advances.
Marketing campaigns
- 1918Spring Offensive defense
Somme and Flanders · France and Belgium
The unit helped delay the German Spring Offensive, destroyed bridges near the Somme, served temporarily as infantry, and constructed defensive trenches and wire obstacles after the Lys breakthrough.
Outcome. The company continued emergency engineering duties until the Armistice.
- 1917Ypres Canal and Passchendaele support
Ypres Salient · Belgium
The company constructed Yorkshire Trench dugout and several associated underground headquarters near Boezinge and the Ypres Canal.
Outcome. The completed dugouts sheltered command formations during the Passchendaele operations and later became important battlefield heritage sites.
- 1916Loos and Hulluch counter-mining
Northern France
From January 1916 to April 1917 the company conducted underground mining and counter-mining around Hill 70, Copse, Double Crassier, and Hulluch on three levels.
Outcome. The sector was later transferred to the 3rd Australian Tunnelling Company after the German mining threat diminished.
- 1915Hill 60
Ypres Salient · Belgium
The company excavated and charged six mines beneath German positions at Hill 60. The group was fired on 17 April 1915 and became the first mine operation of its kind carried out by a Royal Engineers tunnelling company.
Outcome. The detonations created a major underground attack and established the operational importance of British specialist tunnelling units.
- 1915Aubers Ridge
Northern France
The unit worked under I Corps and the Indian Corps to prepare mines beneath German defenses before the Battle of Aubers Ridge, later extending operations toward Rue du Bois and Red Lamp.
Outcome. The tunnelling work supported the British contribution to the Second Battle of Artois.
Brand decisions
1918
Temporary conversion to infantryStrategyBackground
The German Spring Offensive created an immediate manpower and defensive crisis on the Western Front.
Action taken
On 25 March, personnel from the company were converted into infantry as No. 2 Royal Engineers Battalion for emergency operations.
Aftermath
The unit continued both emergency battlefield defense and engineering work, including bridge demolition and the construction of defensive lines.
Recent events
- 2003
Yorkshire Trench dugout is opened to the public[1]
Other
The Yorkshire Trench site, rediscovered and excavated in the late 1990s, was opened to visitors. The dugout had been constructed in the Ypres area by the 173rd or 179th Tunnelling Companies.
- 1916
173rd Tunnelling Company works in the Loos mining sector[1]
Other
The company undertook counter-mining and gallery construction around Hulluch, Loos, Hill 70, Copse, and Double Crassier across several underground levels.
- 1915
173rd Tunnelling Company fires mines beneath Hill 60[1]
Other · Product launch
The company detonated a group of mines under German positions at Hill 60 near Ypres, an operation described as the first mine firing beneath enemy lines by a Royal Engineers tunnelling company.
- 1915
Company supports preparations for the Battle of Aubers Ridge[1]
Other
The unit conducted underground work beneath no man's land and German defenses in preparation for the British attack at Aubers Ridge.
Sources1 sources
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