Tunnel Warfare: The Hidden Frontlines of Combat

By Fouad Sabry

What is Tunnel Warfare

Tunnel warfare is using tunnels and other underground cavities in war. It often includes the construction of underground facilities in order to attack or defend, and the use of existing natural caves and artificial underground facilities for military purposes. Tunnels can be used to undermine fortifications and slip into enemy territory for a surprise attack, while it can strengthen a defense by creating the possibility of ambush, counterattack and the ability to transfer troops from one portion of the battleground to another unseen and protected. Also, tunnels can serve as shelter from enemy attack.

How you will benefit

(I) Insights, and validations about the following topics:

Chapter 1: Tunnel warfare

Chapter 2: Trench warfare

Chapter 3: Lochnagar mine

Chapter 4: Siege of Luxembourg (1684)

Chapter 5: Sapping

Chapter 6: Tunnelling companies of the Royal Engineers

Chapter 7: Hohenzollern Redoubt action

Chapter 8: Mines in the Battle of Messines (1917)

Chapter 9: 175th Tunnelling Company

Chapter 10: 171st Tunnelling Company

(II) Answering the public top questions about tunnel warfare.

Who this book is for

Professionals, undergraduate and graduate students, enthusiasts, hobbyists, and those who want to go beyond basic knowledge or information for any kind of Tunnel Warfare.

• Language: English
• Publisher: One Billion Knowledgeable
• Release date: May 30, 2024

Book preview

Chapter 1: Tunnel warfare

Tunnel warfare is the conduct of combat within tunnels and other underground caverns. It frequently involves the construction of underground infrastructure (mine or undermining) for offensive or defensive goals, as well as the utilization of existing natural caves and manufactured underground facilities for military purposes. Tunnels can be used to undermine defenses and infiltrate enemy territory for a surprise attack, or they can be used to reinforce a defense by creating the option of ambush, counterattack, and the ability to shift men from one area of the battlefield to another without being observed. Additionally, tunnels can provide protection from hostile assault.

Sappers have employed mining against walled cities, strongholds, castles, and other strongly held and fortified military positions since antiquity. The defenders dug countermines to assault miners or destroy mines that threaten their defences. Due to the prevalence of tunnels in metropolitan settings, tunnel warfare is typically a minor aspect of urban warfare. In March 2015, during the Syrian Civil War in Aleppo, insurgents buried a substantial quantity of explosives beneath the offices of the Syrian Air Force Intelligence Directorate.

Tunnels are narrow and restrict fire fields; therefore, there are typically just a few places of a tunnel exposed to fire or sight at any given moment. They can be part of a large labyrinth and contain dead-ends and dim lighting, generally producing a confined night battle situation.

In his Histories, the Greek historian Polybius provides a vivid description of mine and countermining during the Roman siege of Ambracia:

The Aetolians... put up a valiant fight against the attack of the siege guns, so the Romans, in desperation, resorted to mines and tunnels. After securing the middle of their three works and concealing the shaft with wattle screens, they created a 200-foot-long covered walkway or stoa parallel to the wall in front of it, and began digging from there, working in shifts throughout the day and night. When the heap of soil thus removed became too large to be concealed from those within the city, the commanders of the besieged garrison began vigorously digging an interior trench parallel to the wall and the stoa facing the towers. As soon as the trench reached the desired depth, they lined the side of the trench closest to the wall with a row of extremely thin brazen containers and listened for the sound of digging outside as they strolled down the bottom of the trench. Having marked the location indicated by one of these brazen vessels, which were extraordinarily sensitive and vibrated in response to sounds from the outside, they began digging from within, perpendicular to the trench, another tunnel leading under the wall so as to precisely intersect the enemy's tunnel. This was quickly achieved, since the Romans had not only carried their mine up to the wall, but had also underpinned a large length of the wall on either side of their mine, bringing the two groups face to face.

The Aetolians then countered the Roman mine with smoke from feathers burned in charcoal.

Roman sources provide the earliest evidence of the use of tunnels and trenches in guerrilla-style fighting. After the Batavi Revolt, the insurgent tribes quickly shifted from relying solely on local strongholds to taking use of the terrain's expansiveness. Hidden trenches for amassing for surprise attacks were created and linked by tunnels for a safe retreat. In combat, obstacles were frequently employed to block enemy pursuit.

As the ambush of advancing columns resulted in huge deaths, Roman troops invading the region quickly learnt to fear this warfare. Therefore, they approached potentially defended regions with extreme caution, allowing ample time for evaluation, troop assembly, and organization. When the Romans were on the defensive, they utilized the massive underground aqueduct system to defend Rome and evacuate fleeing leaders.

During the Bar Kokhba revolt (132–136 AD), it was popular for Jewish rebels in Judea to employ tunnels as a kind of guerilla warfare against the Roman Empire. The Romans eventually realized that efforts should be made to uncover subterranean tunnels. Once an entrance was identified, fire was lit to either smoke out or suffocate the rebels.

At the citadel of Dura-Europos, which fell to the Sassanians in 256/7 AD during the Roman–Persian wars, well-preserved evidence of mining and counter-mining operations has been uncovered.

At least since the Warring States period (481–221 B.C. ), ancient China employed mining as a siege technique. When opponents sought to construct tunnels under city walls for mining or infiltration, the defenders pumped smoke into the tunnels using large bellows to suffocate the intruders.

In Middle Ages warfare, a mine was a tunnel excavated to destroy castles and other defences. As a response to stone-built castles that could not be torched as easily as earlier-style timber forts, attackers employed this tactic when the stronghold was not constructed on solid rock. Under the outer defenses, a tunnel would be excavated to either enable access to the fortification or bring down the walls. As tunneling progressed, these tunnels would typically be supported by temporary wooden props. Once the excavation was complete, the attackers would collapse the wall or tower by filling the hole with combustible material that, when ignited, would burn away the props, leaving the structure above unstable and so susceptible to collapse.

Engineers use crowbars and picks to excavate at the base of a wall as part of the mining technique of sapping the wall. Peter of les Vaux-de-Cernay describes how, during the Albigensian Crusade, at the battle of Carcassonne, after the top of the wall had been somewhat weakened by bombardment from petraries, our engineers succeeded with great difficulty in bringing a four-wheeled wagon covered in oxhides close to the wall from which they began to sap the wall.

As at the siege of Carcassonne, the defenders attempted to prevent sapping by throwing everything they had at assailants who attempted to dig under the wall. When sapping was successful, the defenders could no longer maintain their position and would surrender, or the attackers may enter the fortress and confront the defenders in close combat.

Several strategies resisted or counteracted subversion. Frequently, the location of a castle can make mining problematic. The walls of a castle could be built on solid rock, sand, or terrain saturated with water, making it difficult to dig mines. As at Pembroke Castle, a very deep ditch or moat may be erected in front of the walls, or even artificial lakes, as at Kenilworth Castle. This makes it harder to dig a mine, and even if a breach is made, the ditch or moat makes it difficult to exploit the breach.

Countermines could also be dug by defenders. Then, they may dig into the assailants' tunnels and enter them to either kill the miners or set fire to the pit-props to collapse the assailants' tunnel. Alternately, they could mine the tunnels of the attackers and create a camouflage to cause the collapse of the attackers' tunnels. Lastly, if the walls were overrun, they may either set impediments, such as a cheval de frise to thwart a desperate hope, or construct a coupure. The inner walls of the huge concentric ringed fortresses, like as Beaumaris Castle on Anglesey, were constructed to be coupures; if an attacker breached the outer walls, he would enter a killing field between the lower outer walls and the higher inner walls.

With the invention of gunpowder in Italy in the 15th century, the art of tunnel warfare underwent a significant transformation, as the reduced effort necessary to breach a wall was accompanied by an increase in lethality.

Ivan the Terrible captured Kazan by using gunpowder explosions to breach its defenses.

Many fortifications constructed anti-mine galleries and listening tunnels to detect the construction of enemy mines. They could be used to detect tunneling from approximately fifty yards away. The Kremlin possessed such tunnels.

Saps have been utilized during assaults on opposing positions since the 16th century.

In his classic work on military matters, the Austrian commander of Italian descent Raimondo Montecuccoli (1609-1680) developed strategies for destroying and countering enemy saps. In his work titled The Assault on Fortifications, Vauban (1633–1707), the founder of the French School of Fortification, outlined a theory of mine attack and how to calculate various saps and the amount of gunpowder required for explosions.

Eduard Totleben and Schilder-Schuldner discussed the organization and execution of underground attacks as early as 1840. They began to disrupt charges using electric current. Complex specialized boring devices were designed.

During the Siege of Sevastopol (1854–1855), underground combat reached epic proportions. Initially, the allies dug saps without taking measures. After a series of explosions produced by counter mine action, the allies expanded the depth of the tunnels, but ran into stony ground and had to return the underground war to higher levels. Russian sappers dug 6.8 kilometers (4.2 miles) of saps and countermines throughout the siege. During the same time frame, the allies excavated 1.3 kilometers (0.81 mi). In the underground combat, the Russians utilized 12 tons of gunpowder while the allies used 64 tons. These numbers indicate that the Russians attempted to construct a more extensive network of tunnels and conducted more precise, less explosive strikes. Due to the use of obsolete fuses by the allies, numerous explosives failed to detonate. In the tunnels, wax lamps frequently extinguished, sappers fainted due to stale air, and ground water filled tunnels and counter mines. The Russians repelled the siege and began tunneling beneath the allies' defenses. Allies acknowledged the Russian triumph in the underground battle. The Times observed that the Russians deserve credit for this type of warfare.

During the Union Army of the Potomac's siege of Petersburg in 1864, a mine containing 3,600 kilograms (8,000 lb) of gunpowder was detonated around 6 meters (20 ft) beneath the sector of Major General Ambrose E. Burnside's IX Corps. The explosion created a crater that was 52 meters (170 feet) long, 30 to 37 meters (100 to 120 feet) wide, and at least 9 meters (30 feet) deep. It ripped a hole in the Confederate defenses of Petersburg,