{"slug": "digging-below-the-death-zone-the-underground-war-in-ukraine", "title": "Digging Below the Death Zone: The Underground War in Ukraine", "summary": "Ukraine and Russia have invested heavily in underground warfare as drone surveillance and AI-assisted targeting make surface movement lethal, with drones accounting for up to 80 percent of battlefield casualties in some sectors like Pokrovsk. The Pentagon, UK Defence Investment Plan, and NATO initiatives reflect a focus on drones, while both armies have expanded trench systems into interconnected tunnel networks, underground command posts, and protected logistics corridors.", "body_md": "If you follow war in any way, you will see innumerable daily [articles](https://www.investing.com/news/world-news/drones-dominate-ukraine-battlefield-four-years-into-fighting-4520564), [podcasts](https://www.csis.org/podcasts/russian-roulette/drones-and-ai-battlefields-ukraine-kate-bondar-and-sam-bendett), and [news stories](https://www.wsj.com/world/ai-powered-drone-swarms-have-now-entered-the-battlefield-2cab0f05) about the prevalence of drones in Ukraine. Pentagon [budget requests](https://www.foxnews.com/politics/pentagon-jumps-from-225m-55b-drones-cheap-attacks-overwhelm-us-defenses) reference it. So does the UK’s [Defence Investment Plan](https://assets.publishing.service.gov.uk/media/6a44e989167a99cf0018da38/The_Defence_Investment_Plan.pdf). [NATO initiatives](https://www.nato.int/en/news-and-events/articles/news/2026/07/07/nato-allies-invest-40-billion-dollars-in-counter-drone-capabilities-and-drone-training) increasingly reflect the same focus. Defense [conferences center](https://www.smgconferences.com/defence/northamerica/conference/loitering-munitions-usa) entire panels around the lessons of first-person-view drones, loitering munitions, and AI-enabled targeting. Reporting regularly highlights Ukraine’s ability to produce [thousands of drones](https://www.kyivpost.com/post/73860) each week and potentially millions each year. The war has become synonymous with the transparent battlefield, where anything that moves can be seen and killed.\n\nBut while the world watched the skies over Ukraine, another transformation in warfare was taking place beneath the ground. Ukraine and Russia started investing heavily in underground warfare. Both armies have adapted to a battlefield where survival increasingly depends on getting below the surface. Expanded trench systems [have grown into](https://www.wsj.com/world/europe/ukraine-defense-construction-russia-war-d72f2d29) interconnected tunnel [networks](https://www.rferl.org/a/ukraine-front-lines-trenches/32859005.html), underground command posts, protected logistics corridors, [buried medical facilities](https://www.army.mil/article/287994/the_ukrainian_underground_lessons_for_medcom_sustainment_in_lsco), [drone production sites](https://inkstickmedia.com/from-florist-to-drone-maker-the-civilians-arming-ukraines-drone-war/), and [infiltration routes](https://www.businessinsider.com/ukraine-russian-troops-underground-gas-water-pipe-kupiansk-flood-2025-9) beneath contested terrain across the front lines.\n\nToday’s battlefield is more lethal than at any time since World War I. Jam-proof, fiber-optic drones equipped with thermal cameras hover continuously over supply routes, trench lines, artillery positions, and troop concentrations. Satellite surveillance, persistent reconnaissance, acoustic detection systems, and AI-assisted targeting have dramatically shortened the kill chain, the time between detection and destruction. Ukrainian unmanned systems and persistent surveillance have fundamentally altered survivability on the battlefield by making concealment and movement intensely difficult. Along the Ukrainian front line, soldiers describe a “[death zone](https://www.independent.co.uk/news/world/europe/russian-troops-ukraine-dnipro-delta-river-death-zone-b2850629.html)” of some [thirty kilometers](https://www.reuters.com/graphics/UKRAINE-CRISIS/KILL-ZONE/znpnojmknvl/) where movement above ground can trigger attack within minutes. Reporting from Ukraine’s Pokrovsk described drones accounting for as many as [80 percent](https://www.lemonde.fr/en/international/article/2025/04/10/in-pokrovsk-ukraine-the-underground-war_6740043_4.html) of battlefield casualties in some sectors.\n\nWhenever firepower makes the surface too lethal, armies go underground, whether for protection or to create another axis of maneuver. World War I saw extensive mining and tunnel operations beneath the trench systems that stretched from [Messines Ridge](https://www.history.com/articles/battle-messines-world-war-i-tunnels) in southern Belgium to the [Somme](https://tv.apple.com/us/episode/the-secret-of-the-somme/umc.cmc.66f69erw96tmjypemwn2wcuvw?showId=umc.cmc.2qmpyt4pe4tq3f1wy5eo0h99e) region of northern France along the Western Front, and the same was seen in the glaciers and Alpine mountains of the [Italian Front](https://en.wikipedia.org/wiki/Mines_on_the_Italian_front_(World_War_I)). During the Vietnam War, the Viet Cong constructed extensive tunnel networks, most famously around Cu Chi and the Iron Triangle northwest of Saigon. The Cu Chi system alone eventually extended [approximately 250 kilometers](https://www.history.com/articles/cu-chi-tunnels) and included interconnected tunnels containing command posts, hospitals, workshops, storage areas, and fighting positions that enabled communist forces to survive American firepower, sustain logistics, and maneuver with reduced risk of detection. Hamas spent decades constructing [hundreds of kilometers](https://www.washingtonpost.com/national-security/2024/10/05/hamas-tunnels-weapons-gaza-war-october-7-attacks/) of underground military infrastructure beneath Gaza and used that network as a central component of its [politico-military strategy](https://mwi.westpoint.edu/gazas-underground-hamass-entire-politico-military-strategy-rests-on-its-tunnels/) during the ongoing Israel-Gaza conflict. Hezbollah also built [hardened tunnel systems](https://www.reuters.com/world/middle-east/hezbollahs-tunnels-flexible-command-weather-israels-deadly-blows-2024-09-25/) across southern Lebanon, reportedly with assistance from North Korea and Iran. North Korea itself is believed to maintain one of the most extensive underground military infrastructures in the world. US estimates range from [five thousand to eight thousand underground sites](https://www.stripes.com/theaters/asia_pacific/report-us-has-mapped-north-korean-underground-escape-facilities-1.361678#.WQecN1KZMUQ), including invasion tunnels, leadership bunkers, artillery positions, troop shelters, and three major [underground air bases](https://www.dailynk.com/english/north-korea-constructs-underground/), one of which reportedly contains a [1,800-meter runway](https://www.googlesightseeing.com/2008/05/north-koreas-thunderbird-runways/#google_vignette) running through a mountain. Recent operations against Iran have again demonstrated how extensive underground facilities can provide [structural resilience](https://www.army.edu/News/View/Article/4421735/ssi-live-122-on-iran/) against overwhelming airpower and precision weapons.\n\nUkraine represents the latest evolution of this recurring pattern. Both Ukraine and Russia have adapted to the growing transparency—and consequently, growing lethality—of the surface battlefield by expanding their use of the underground, while also drawing on lessons from the increasingly sophisticated underground systems seen in the Middle East and other recent conflict zones. What distinguishes Ukraine is the scale and range of that adaptation.\n\nUkraine has constructed increasingly sophisticated underground systems connecting trench networks, fighting positions, command nodes, and logistics hubs. Many go well beyond improvised field fortifications and require specialized engineering expertise, heavy equipment, and large quantities of steel and concrete. Reports from eastern Ukraine describe hardened, multilevel [underground facilities](https://www.theguardian.com/world/2025/oct/25/underground-hospital-ukrainian-soldiers-injured-by-russian-drones) equipped with fiber-optic communications, ventilation systems, reinforced concrete protection, and concealed corridors that allow troops to move between positions without exposure to drones overhead. Russian forces have developed similar systems. Near Zaporizhzhia and elsewhere, Russian troops reportedly constructed extensive [underground corridors](https://united24media.com/latest-news/ukraine-drones-and-missiles-made-rear-areas-a-myth-so-russias-hqs-dig-in-underground-video-16192), some capable of accommodating vehicles, with reinforced passageways designed to withstand artillery strikes and first-person-view drone attacks.\n\nThat evolution did not occur all at once. During the first days of the war, civilians and military forces in several major cities relied heavily on preexisting urban underground spaces, particularly [subway systems](https://www.reuters.com/news/picture/safety-in-the-subway-life-inside-kyivs-c-idJPRTSFK38J/), for shelter. As the war continued, underground construction expanded first at the tactical level through deeper trench systems and protected fighting positions. Continued Russian precision strikes and persistent drone surveillance then drove a much broader transformation. Underground facilities increasingly supported operationally focused [command and control](https://news.sky.com/video/inside-ukraines-underground-military-hq-13480256), logistics, manufacturing, medical treatment, and civil defense, with many projects built by civilian construction companies using commercial engineering equipment rather than military engineers alone. Many of these facilities [go deeper](https://www.forbes.com/sites/davidkirichenko/2026/03/04/excavators-are-building-ukraines-drone-era-fortifications/) and are larger than military engineers typically build, forcing Ukraine to rely on civilian tunneling and construction firms. Such knowledge and expertise are unlikely to be available at scale within a conventional military engineering enterprise.\n\nUkraine’s underground engineering and specialized construction sector includes firms focusing on tunneling, geotechnical works, and underground utilities, all of whom have been brought in to support the war effort. An example of such a project was the [Pokrovsk](https://www.youtube.com/watch?v=1-GOUmZy-sg&t=12s) underground facility in the Donetsk region where the [Automagistral-Pivden Company](https://automagistral.com.ua/en/budivnytstvo-ob-iektiv-zakhystu/) has developed a complex extending thirty kilometers. Further examples include [Metinvest](https://gmk.center/en/news/metinvest-has-built-a-second-underground-hospital-with-a-new-configuration-for-the-armed-forces-of-ukraine/), which has built several underground hospitals, and the Ukrainian Association of Developers, a group of real estate and construction companies, which has built several facilities and connecting underground [access routes](https://thedefensepost.com/2026/01/29/ukraine-underground-fortifications-frontline/). The ability to rapidly create underground infrastructure has become integral to protecting combat power on a transparent battlefield. This is evident in the development of NATO’s [Eastern Flank Defensive Initiative](https://www.europeafrica.army.mil/What-We-Do/INNOVATION/EFDI/).\n\nBut while those efforts were largely focused on the development of new underground spaces, there has been the opportunity to exploit existing infrastructure. One of the clearest examples emerged through repeated Russian attempts to use pipelines and underground conduits for infiltration operations. In March 2025, Russian special operations forces reportedly moved through sections of the disused Urengoy-Pomary-Uzhhorod gas pipeline during operations near [Sudzha in Kursk Oblast](https://www.reuters.com/world/europe/russia-uses-gas-pipeline-surprise-ukrainian-forces-kursk-bloggers-say-2025-03-09/) as part of an effort to infiltrate behind Ukrainian positions. The Institute for the Study of War assessed that Russian units attempted to exploit [underground pipeline](https://understandingwar.org/research/russia-ukraine/russian-offensive-campaign-assessment-september-13-2025/) infrastructure to support surprise assaults against Ukrainian defensive positions. Additional reporting near Kupiansk described Russian troops using underground gas and water pipelines to bypass drone surveillance and frontline observation, forcing [Ukrainian units](https://www.businessinsider.com/ukraine-russian-troops-underground-gas-water-pipe-kupiansk-flood-2025-9) to adapt by damaging, flooding, mining, and fortifying the pipelines while monitoring entrances and exits with drones and thermal surveillance for ad hoc ambush opportunities.\n\nIn some cases, [underground infiltration](https://www.forbes.com/sites/vikrammittal/2026/06/12/russia-adopt-new-infantry-tactics-in-attempt-to-regain-momentum/) contributed directly to operational success. Before the [capture of Avdiivka](https://www.nytimes.com/2024/02/17/world/europe/avdiivka-russia-ukraine-war.html) in 2024, Russian troops reportedly spent several days clearing and preparing an infiltration route through several kilometers of sewer pipe approximately 1.4 meters in diameter. These operations sound primitive, almost medieval. Instead, they represent the collision of ancient mine and tunnel warfare with twenty-first-century surveillance technology. The battlefield has become so transparent that soldiers increasingly seek protection and concealment below ground, even if it means crawling for kilometers through narrow and toxic industrial pipes. What matters is avoiding the overhead drones.\n\nThe underground networks themselves continue to evolve rapidly. Ukrainian positions connect through tunnel systems designed specifically to defeat persistent drone surveillance, allowing troops to move between firing positions and command centers without exposing themselves to aerial observation. Ukraine has also moved portions of its war-supporting infrastructure underground. Ukrainian forces have built [underground manufacturing and logistics sites](https://www.theguardian.com/world/2025/oct/25/underground-hospital-ukrainian-soldiers-injured-by-russian-drones) that assemble first-person-view drones, repair equipment, store munitions, and operate distributed logistics nodes beneath damaged buildings and hardened positions. This adaptation reflects a broader lesson emerging from Ukraine: Centralized infrastructure is increasingly vulnerable on transparent battlefields. Distributed and concealed infrastructure survives longer, making dispersed command and control, scattered logistics, and [decentralized production](https://rusi.org/explore-our-research/publications/special-resources/return-industrial-warfare) increasingly important for survival against modern precision-strike systems.\n\nMedical operations have moved underground as well. Many Ukrainian hospitals now operate several meters below the surface [near the front lines](https://www.washingtonpost.com/world/2025/06/15/ukraine-underground-hospital-war-russia/) with operating rooms, ventilators, trauma stations, and surgical teams treating casualties while artillery and drones strike overhead. [Doctors describe](https://www.theguardian.com/world/2025/oct/25/underground-hospital-ukrainian-soldiers-injured-by-russian-drones) first-person-view drones as the leading source of battlefield injuries, with amputations and fragmentation wounds now routine. The underground protects medical personnel and wounded soldiers from artillery, drone attacks, and glide bombs that have increasingly targeted above-ground facilities and medical evacuation services.\n\nThe same engineering capability has extended rearward from frontline positions. Civil defense organizations have begun constructing hardened underground shelters for urban populations, including modular steel [“Citadel” bunkers](https://odessa-journal.com/public/ukraine-builds-its-first-new-type-of-underground-steel-bunker-for-civilians--the-citadel#google_vignette) intended to protect civilians from missile and drone attack. These projects illustrate that Ukraine’s underground adaptation now extends well beyond tactical survivability. Industrial production, medical care, and civilian protection are increasingly being relocated beneath the surface as part of a broader effort to preserve national resilience under sustained precision attack.\n\nRussia has also adapted its weapons and tactics to attack increasingly sophisticated underground positions, particularly through the use of [thermobaric weapons](https://www.youtube.com/watch?v=t8VsogNvmaI). Weapons such as the [TOS-1A](https://oe.t2com.army.mil/product/russias-thermobaric-weapons-employment-in-the-ukrainian-conflict/) are especially dangerous in confined spaces because they weaponize pressure and oxygen depletion rather than relying solely on fragmentation. Thermobaric weapons amplify blast pressure and oxygen depletion effects, making tunnels and enclosed structures uniquely vulnerable to these systems. Tunnel systems that can survive artillery strikes may still become death traps under thermobaric attack, unless enhanced protection engineering and design can be introduced. A notable use of such a weapon in an anti-tunnel role was the GBU-43/B [MOAB](https://www.bbc.co.uk/news/world-asia-39598046) (known as the “mother of all bombs”) airstrike by the United States against Islamic State group militants located inside a cave network in Afghanistan in 2017.\n\nUnderground warfare also changes how armies detect each other. Above ground, modern combat intelligence, surveillance, target acquisition, and reconnaissance is dominated by a complex suite of surface, aerial, and space-based sensors. While these sensors still play a part, alongside other traditional forms of intelligence gathering, underground warfare locally shifts toward sound, vibration, and the physical properties of the ground within which subterranean facilities and structures exist. Geophysical and acoustic sensor systems, linked to underground modeling and mapping technologies, and a sophisticated understanding of the host geology have become increasingly important for detecting voids, movement, digging, generators, and troop activity beneath the surface. Once detected, targets can be generated and fed into the strike enterprise—although a persistent challenge is how to do this at range due to the limitations of some sensors.\n\nDetecting and striking underground targets from a distance, however, addresses only part of the problem. Ground forces may still have to locate, enter, clear, and control underground spaces, compressing the subterranean *detect-understand-strike-kill* [chain](https://en.wikipedia.org/wiki/Kill_chain_(military)) into a much smaller area and much shorter period of time. The challenge becomes even greater in dense urban environments, as recent [operations in Gaza](https://www.army.mil/article/288356/subterranean_operations_israeli_defense_force_lessons_from_gaza) and [Lebanon](https://www.i24news.tv/en/news/israel/defense/artc-idf-uncovers-major-hezbollah-tunnel-complex-beneath-southern-lebanese-village) have demonstrated.\n\nTechnology is transforming the underground fight as well. Underground combat is widely regarded as one of the most dangerous forms of warfare because personnel are not only fighting the enemy, but also the [environment](https://mwi.westpoint.edu/urban-warfare-project-podcast-underground-warfare-reimagined/). One of the most important developments has been the increasing use of unmanned systems inside tunnels and confined underground spaces before a human or a military working dog enters, essentially *metal-before-flesh* tactics, techniques, and procedures. Unlike surface systems, underground systems cannot necessarily rely on GPS or stable radio communications. The underground requires specialized unmanned systems with inertial guidance or [simultaneous localization and mapping](https://medium.com/@xiaxiami/understanding-slam-simultaneous-localization-and-mapping-in-robotics-3592eb504f11) technology, and either self-meshing radio communications, or umbilicals, which may of course provide power as well as communications.\n\nThe technological challenges of operating underground were recognized well before the wars in Ukraine and Gaza. From 2018 to 2021, DARPA’s [Subterranean Challenge](https://www.darpa.mil/news/2019/subterranean-challenge-urban-circuit-location) focused on autonomous robotic systems and sensor technologies designed specifically for underground environments where GPS and traditional communications fail. The war in Gaza has demonstrated how quickly these technologies [must be adapted](https://mwi.westpoint.edu/israels-new-approach-to-tunnels-a-paradigm-shift-in-underground-warfare/) under combat conditions, driving advances in robotics, communications, engineering, and underground tactics.\n\nBeyond equipment and tactics, the psychological and physiological effects of prolonged periods underground can be severe. These include claustrophobia, exhaustion, disrupted sleep cycles, and other effects stemming from isolation from sunlight and normal human rhythms. During World War I, similar conditions produced what many soldiers described as “[mine madness](https://www.jstor.org/stable/j.ctt9qf3st)” and psychological distress among units tasked with developing mines or fighting underground. These psychological effects were also identified among the specialist “[Tunnel Rats](https://history.army.mil/Portals/143/Images/Publications/Publication%20By%20Title%20Images/C%20Pdf/combat-taking-the-offensive.pdf)” during the Vietnam War and have also been documented among [Israeli soldiers](https://www.tandfonline.com/doi/full/10.1080/13537121.2021.1940550) training for and conducting subterranean operations, where stress, claustrophobia, cognitive impairment, and the unique psychological demands of underground combat have become important considerations. The same is seen in the Ukrainian [civilian population.](https://www.unicef.org.uk/press-releases/frontline-children-battling-mental-trauma-underground/)\n\nNATO militaries are not prepared for this future. To be sure, the US Army recognized aspects of the underground challenge nearly a decade ago and built limited training facilities and explored investments in underground preparation. But much of that effort focused narrowly on tunnel detection, clearance, and denial rather than occupying and operating in tunnels.\n\nThe US Army developed operational doctrine in 2019 ([Army Techniques Publication 3-21.51, Subterranean Operations](https://documents2.theblackvault.com/documents/army/ARN19656_ATP.pdf)), which provided a foundation for the British Army’s doctrine in 2020 (Doctrine Note 20/05,\n\n*Subterranean Operations in the Urban Environment*). However, in both cases, the doctrine overly emphasized how to classify and then enter and clear tunnels. Neither provided guidance on rapidly constructing or repurposing underground infrastructure, integrating underground maneuver into combined arms warfare, or sustaining formations beneath the surface during prolonged conflict. In 2018, the US Army’s spent nearly\n\n[half a billion dollars](https://www.military.com/daily-news/2018/06/24/army-spending-half-billion-train-troops-fight-underground.html)preparing brigades for underground combat operations. But at present, no NATO partner maintains specialist or even generalist capabilities for large-scale underground warfare, despite years of acknowledging the threat.\n\nCombat training centers rarely have extensive underground infrastructure and units still rarely train seriously for underground warfare. Even where tunnel systems exist in urban training areas, they are often [underused](https://mwi.westpoint.edu/urban-warfare-project-podcast-nato-urban-training-sites/) because commanders worry they will slow exercises or complicate broader training objectives. Unfortunately, the future battlefield will not simplify itself for the convenience of training schedules or to ensure a no-fail record.\n\nThat gap matters because underground warfare is no longer confined to Gaza or niche counterterrorism operations. It is already prominent in Ukraine, Iran, Lebanon, and Syria, and it would almost certainly shape future conflicts involving Taiwan or the Korean Peninsula. The well-known British military theoretical and historian [Captain Sir Basil Liddell Hart](https://en.wikipedia.org/wiki/B._H._Liddell_Hart) argued that armies too often fail to learn the enduring lessons of war, only to rediscover them at great cost in the next conflict. Underground warfare is becoming another of those recurring lessons.\n\nThe underground now serves many functions on the modern battlefield. Forces maneuver through it, manufacture equipment inside it, establish headquarters in it, treat casualties there, and increasingly fight for control of it. It has become one of the most effective counters to the transparent battlefield created by drones, persistent surveillance, and precision strike.\n\nThe lesson from Ukraine is clear. Drones, sensors, satellites, and AI have made surviving above ground dramatically harder. Armies are responding the same way armies always have when firepower dominates the surface: They are moving underground. NATO and its partners should adapt doctrine, training, force design, and investment accordingly, before the next conflict forces them to relearn the lesson. Armies that cannot survive above ground must adapt below it.\n\n*John Spencer is chair of urban warfare studies at the Modern War Institute, codirector of MWI’s Urban Warfare Project, and host of the *Urban Warfare Project Podcast*. He served twenty-five years as an infantry soldier, which included two combat tours in Iraq. He is a founding member of the **International Working Group on Subterranean Warfare**.*\n\n*Colonel (OF5) Drew Craig is the principal Military Engineering Staff Officer to NATO’s Allied Rapid Reaction Corps (ARRC). Over thirty years’ service, including an operational tour of Iraq, he has served in a range of roles, including geospatial intelligence, infrastructure support, explosive ordnance disposal and search, and civil-military cooperation. He developed an interest in subterranean operations while serving as the British Army’s principal geologist and has written and lectured on this subject for the past eight years. **He is a founding member of the **International Working Group on Subterranean Warfare**.*\n\n*The views expressed are those of the authors and do not reflect the official position of the United States Military Academy, Department of the Army, or Department of Defense, or those of any organization the authors are affiliated with, including the British Army, the UK Ministry of Defence, or the British government.*\n\nImage credit: [Mil.gov.ua](https://commons.wikimedia.org/wiki/File:47th_brigade_trench_fight_near_avdiivka.png)", "url": "https://wpnews.pro/news/digging-below-the-death-zone-the-underground-war-in-ukraine", "canonical_source": "https://mwi.westpoint.edu/digging-below-the-death-zone-the-underground-war-in-ukraine/", "published_at": "2026-08-12 13:24:58+00:00", "updated_at": "2026-08-12 13:45:32.249393+00:00", "lang": "en", "topics": ["artificial-intelligence", "ai-policy", "ai-ethics"], "entities": ["Pentagon", "NATO", "Ukraine", "Russia", "UK Defence Investment Plan"], "alternates": {"html": "https://wpnews.pro/news/digging-below-the-death-zone-the-underground-war-in-ukraine", "markdown": "https://wpnews.pro/news/digging-below-the-death-zone-the-underground-war-in-ukraine.md", "text": "https://wpnews.pro/news/digging-below-the-death-zone-the-underground-war-in-ukraine.txt", "jsonld": "https://wpnews.pro/news/digging-below-the-death-zone-the-underground-war-in-ukraine.jsonld"}}