March 23rd, 1918 began as a routine day in Paris. The city’s infrastructure and population were functioning according to their usual schedule. At 7:16 a.m. in the central part of the capital at the Plasta La Republic, the first explosion occurred. Soon, with intervals of about 20 minutes, strikes followed in other districts.

 The shelling continued every 15 to 20 minutes, destabilizing the situation in the city. The French command faced difficulties determining the source of the attack. German positions were located over a 100 kilometers away, while the maximum artillery range of that period was limited to 30 km. This technical discrepancy created a complex tactical challenge for military specialists attempting to establish the origin of the threat.

 Sound ranging stations didn’t pick up the sound of gunfire, and reconnaissance aircraft failed to spot any new enemy artillery batteries setting up. With no visible source of fire, the origin of the shells remained a mystery. The source of the bombardment was located 120 kilometers from Paris in the woods near the town of Krei.

 Located there was a massive artillery unit with a barrel 34 meters long mounted on a reinforced railway platform. Due to its significant length and weight of 138 tons, the barrel would warp under its own weight. So, a support system of steel cables was used to hold it in place and keep its shape. This weapon known as the Paris gun was a secret development by the Crook Concern.

 Design on the system began in 1914 when engineers were tasked with the technical challenge of creating a gun capable of hitting targets in Paris from a distance of over a 100 kilometers. The use of this weapon had less to do with tactics and more to do with psychology, aiming to demonstrate the capital’s vulnerability.

 Calculations showed that reaching the required range called for a barrel at least 34 m long, but the technology of the time made it impossible to cast a single piece of that size. The technical solution was to use worn out 380 mm naval gun barrels from battleships known as Longmax. Their interiors were bored out to install rifled liners, reducing the caliber to 210 mm.

 This composite design allowed for the necessary length, but operational challenges emerged during the process. Weighing over 100 tons, the barrel sagged under its own weight. Engineers developed a support system with steel cables resembling a crane boom. After every shot, the barrel would wobble for two or three minutes, and the crew was forced to wait for the vibrations to die down.

 When the firing was over, the gun was dismantled for straightening as the heat and stress caused deformationation. A characteristic feature of the system was the extremely rapid wear of the barrel bore. Gases from the combustion of a 196 kg charge and the friction of a 20 kg shell increased the tube’s diameter with every shot.

 The initial 210 mm caliber would widen to 214 mm after just a few dozen launches. German engineers applied a technical solution involving numbered shells and a gradual increase in their diameter. The caliber of the first round was 210 mm while subsequent ones were manufactured with a slight thickening. Firing was conducted in a strict sequence to compensate for bore wear ensuring the shell traveled correctly and maintained the necessary seal.

 The lifespan of each barrel was limited to a range of 65 to 68 shots after which the component had to be replaced. The project saw the production of seven barrels distinguished by their highcost and complex manufacturing process. Replacing a worn component was a laborintensive operation involving crane equipment and took several days.

 The 256 ton artillery system was positioned on a specialized railway platform providing for transport and the changing of firing positions. Preparing to fire was a complex multi-step technical process. Specialists would visually inspect the inside of the barrel using lights to spot any potential deformationations. Next, ballistic calculations were performed based on current weather data, including wind conditions at various altitudes, temperature, humidity, and atmospheric pressure.

 Any inaccuracy in the math could lead to the impact point drifting significantly. The ammunition was made of tough steel designed to withstand extreme G forces during acceleration. The explosive charge weighed 15 kg. Most of the weight came from the reinforced casing which was needed to keep the shell intact as it flew through the stratosphere.

 Once all preparations were complete, the gun was fired. Leaving the barrel at a speed of over 1 and a half kilometers per second, the shell climbed a steep ballistic trajectory. 20 seconds later, it reached an altitude of 20 km, breaking through the troposphere and moving into the stratosphere.

 Another minute later, the object hit the highest point of its flight, 40 kilometers above the Earth. At that altitude, in the thin atmosphere and temperatures around 50° below zero, the shell passed its apogee and began its descent. As it re-entered the dense layers of air, friction heated the casing to extreme temperatures before it finally struck its target within the city limits of Paris.

 The total flight time was about 3 minutes, covering a distance of 120 km. accuracy remained poor. The technical limitations meant only large area targets could be hit as the probable error of the shells was measured in kilometers. Given these limitations, this artillery piece was hardly suitable for hitting specific military targets like barracks, warehouses, or headquarters.

 Instead, the system was used primarily as a tool for psychological warfare against civilians. Shells landed in random parts of the city, creating an atmosphere of total unpredictability. The inability to predict where the next strike would hit was destabilizing as any civilian building could suddenly be destroyed.

 The government faced a crisis and panic spread among the people of Paris. With no information on the source of the threat or how to stay safe, a mass evacuation of the capital began. A huge number of citizens fled their homes, clogging transport routes, shutting down factories, and temporarily paralyzing the city’s economy. The Germans strategic goal wasn’t so much the physical destruction of the city’s infrastructure, but rather to exert psychological pressure on the population.

 In total, 303 shells were fired at Paris, killing 256 people and wounding 620. Compared to the front lines where daily casualties could reach the tens of thousands, these numbers were relatively small. But the demoralizing effect was significant. The French command scrambled to find ways to counter the threat. Attempts to locate the gun using sound ranging stations failed due to the extreme firing range.

Aerial reconnaissance couldn’t find the target either since the gun was camouflaged in the woods and hidden by smoke screens whenever it fired. Military leadership demanded that intelligence services find the object’s exact location. The decision was made to drop agents behind enemy lines into territory controlled by the opposition.

The first plane carrying two scouts searched for a landing spot but was forced to return to base. The second plane was shot down by German anti-aircraft fire, killing the agents on board. Despite the loss of time and lives, the shelling of the capital continued just as relentlessly as before.

 Later, an agent operating inside Germany managed to locate the secret weapon. The intelligence was passed through secure channels to Paris, and French command ordered a strike on those coordinates. For three days, artillery pounded the area, firing thousands of shells at the enemy’s suspected positions. The gun crews kept up a continuous fire, burning through massive amounts of ammunition, trying to destroy the enemy weapon.

 As it turned out, the data was either wrong or a piece of disinformation planted by German counter intelligence. The target coordinates were 5 miles away from where the Paris gun actually sat. Consequently, the French resources were wasted for nothing, while the German gun remained operational and continued to function. The German command, anticipating their position might be discovered, had developed a complex camouflage system.

About 30 artillery batteries of different calibers were deployed around the site, ordered to fire at the exact same moment as the main gun. At the moment the Paris gun fired, a volley from multiple other guns was launched along that sector of the front. The interference of sound waves created a complex acoustic environment that prevented French sound ranging stations from isolating the specific source.

Operators registered the simultaneous firing of dozens of batteries, making it technically impossible to identify the super heavy weapon. Along with sound masking, visual concealment was used. The position was surrounded by trees and camouflage nets. During firing, smoke screens were deployed at multiple points to hide the muzzle flash and hinder visual observation.

 The railroad tracks leading to the position were disguised as ordinary forest roads. Not even the personnel of neighboring German units were informed of the gun’s existence. Strict secrecy was enforced by specially selected guard units whose soldiers were sworn to silence under threat of execution. Outsiders were barred from the site under the guise of it being an ammunition depot or command post.

 Access to the zone was strictly regulated. Operating this artillery system demanded significant resources. The crew consisted of specialized experts. artillerymen, mechanics, ballistics officers, and meteorologists. Preparing for each shot was a lengthy process. First, based on data from multiple stations, they compiled an atmospheric forecast for altitudes up to 40 kilometers.

 Then came the necessary ballistic calculations performed using slide rules and tables. Mechanics inspected the gun assembly, checked the tension on the support cables, and lubricated the targeting mechanisms. A separate team handled the ammunition preparation. Rounds were brought in from a secure bunker, inspected for defects, and the shell numbers were verified to ensure the correct firing sequence.

 The loading process was a technically complex operation due to the sheer weight of the components. The 120 kg projectile was hoisted by winch and guided into the brereech. Any damage to the rifling was strictly forbidden as it risked jamming the shell or causing the barrel to burst. Following the projectile, a powder charge weighing 196 kilograms packed into several silk bags was loaded in.

 The breach was locked by a massive bolt that required the combined effort of several men to close. Once readiness was checked and calculations verified, the commander gave the order to fire. Activating the firing mechanism was accompanied by a loud roar and a massive burst of flame. The recoil caused the platform to vibrate and the ground to tremble over a wide radius while the movement of the barrel continued for several minutes after the shot.

 Every 20 to 30 rounds, a technical pause was needed to clear the barrel of carbon buildup and shell casing residue. Specialized teams spent long periods inside the mechanism, removing deposits using both mechanical tools and chemicals. The working conditions for the technical crew were complicated by high temperatures and a concentration of toxic gases in the confined space which took a toll on their health.

 Nevertheless, operation of the weapon continued according to the established schedule. Experts questioned the practicality of the system due to its high resource consumption. Producing the ammunition required expensive materials and precision machining. The gunpowder used for a single shot was comparable to the daily supply of an ordinary artillery battery.

 The barrel wore out after roughly 60 shots, and the cost of replacing it was equivalent to the expense of building a small warship. Supporting the large crew of skilled specialists, guarding the positions with an infantry company, as well as the camouflage and redeployment efforts required significant resources. According to estimates, these assets could have been used much more effectively on the front lines.

 German artillery officials calculated that the expense of creating and maintaining the gun was comparable to the cost of dozens of standard heavy batteries. Batteries that could have inflicted far greater damage on the enemy. The final results were 303 shells fired, 256 dead, and 620 wounded.

 Military experts considered these statistics unsatisfactory. The cost of a single shot exceeded the monthly expense of maintaining an infantry company. While the effectiveness of the fire remained limited, a significant portion of the shells landed in the suburbs or outside the city limits, hitting vacant lots and causing no damage to infrastructure.

Some rounds exploded over the river or struck already destroyed buildings and empty parks. Nevertheless, Germany’s political leadership, led by Kaiser Wilhelm II, had a different view on the viability of this weapon. In Germany, this long range gun was viewed as a symbol of their high military technical potential.

 It was believed that their engineers had created a unique system that far outclassed the weaponry of other nations. The ability to hit targets from over a 100 kilometers away was held as a major technological breakthrough. German propaganda seized on this, highlighting just how vulnerable the enemy was. The press ran stories about the destabilization of Paris, the exodus of its population, and the authorities struggle to keep control.

 The psychological impact of the shelling was substantial. The unpredictability of where the shells would land kept the city on edge, disrupting the rhythm of daily life and the work of institutions. Among the residents, rumors circulated about high altitude aircraft or airship since no groundbased source for the attacks could be seen.

 The French leadership held back from officially denying these rumors. To confirm the existence of such an artillery system would have been an admission that they had no effective defense against it. Meanwhile, German specialists continued their work on modernizing the gun, testing various types of ammunition to improve their effectiveness.

 They looked into options with more explosives, shrapnel elements, and even chemical payloads. However, attempts to make the warhead more lethal ran into physical limitations. The shell casing had to be incredibly strong to withstand the G forces at launch and the extreme heat of passing through the stratosphere. Any reduction in structural integrity led to the ammunition tearing itself apart inside the barrel or mid-flight.

 Several test runs ended in disaster. The shells detonated mid-flight, never reaching their targets, while fragments rained down on German occupied territory. In the spring of 1918, the German command launched a major offensive on the Western Front, aiming to break the Allied defense lines and take Paris before the full force of the US military could enter the conflict.

 The Paris gun was designed to support this operation by putting pressure on the government and the people of the French capital. The shelling intensified, sometimes reaching 10 rounds a day. The worst incident occurred on March 29th, Good Friday, when a shell struck the church of San during a service. The building collapsed, killing 88 people, including women and children.

 This was the single deadliest event during the gun’s entire operation and caused a massive international outcry. Yet, the German offensive failed to achieve its goals. Allied troops reinforced by American units repelled the attacks and launched a counteroffensive. By August 1918, the strategic situation for Germany had deteriorated.

 Armies began retreating all along the Western Front, abandoning occupied territories and pulling back toward the borders. There was a real threat that the artillery piece would be captured by advancing enemy troops. The firing position was getting closer to the front line, and the likelihood of a defensive breakthrough was growing.

command made the decision to evacuate the equipment to the rear. Dismantling and transporting such a massive weapon was a complex logistical operation. Dismantling the weapon involved using cranes to hoist the barrel off the carriage, then breaking down the platform into sections so it could be moved.

 This all had to happen under the constant threat of enemy air raids and artillery fire. Most of the work was done at night under artificial lights, carefully shielded by camouflage. The crew worked fast to keep the gun from falling into the hands of advancing troops. Ultimately, the Paris gun was taken apart, loaded onto trains, and shipped deep back into Germany.

 The final shot at the French capital was fired on August 9th, 1918. And after that, the weapon was pulled out of the combat zone for good. As the German forces retreated, French intelligence stepped up the search, scouring abandoned positions for any trace of the artillery system. At the firing sites, they found concrete foundations, sections of track, and empty ammo crates, but the gun itself was gone.

 The main equipment had been evacuated just in time, leaving only minor scraps behind. Engineers studied these fragments to try and reconstruct the device, but they had very little information to go on. Examining a few unexloded shells in the lab gave them a rough idea of the systems capabilities, but that was all.

 On November 11th, 1918, the armistice was signed, ending the First World War. Following Germany’s surrender, Allied representatives were granted the right to inspect military sites and confiscate weaponry. Special commissions were dispatched to hunt down and seize examples of advanced military technology, including this elusive long range gun.

 The French side insisted on the handover of this weapon. They intended not only to study its design, but also to display it as a trophy. symbolizing Germany’s military defeat. However, the search efforts yielded no results. The German command denied the existence of any ultra-long range artillery and provided no information about its location.

 Allied inspectors scoured German arsenals, the corrupt factories, railway depots, and military warehouses. During these checks, they discovered a multitude of weapons ranging from small arms to heavy howitzers. Yet the specific unit they sought was missing. Industrial employees claimed to have no information about such a project, and no blueprints or technical documentation could be found in the military archives.

 The situation raised doubts about the reality of the story regarding the shelling of Paris. Even though physical traces of impacts and eyewitness accounts confirm the fact that such a weapon had been used, German representatives refrained from commenting, refusing to discuss the subject, even under the threat of sanctions.

 The most plausible hypothesis is that the German command ordered the destruction of all traces of the installation immediately after the end of combat operations. The gun represented the cutting edge of German military engineering and the leadership strove to prevent this technology from falling into the hands of their opponents.

 It is assumed that the barrels were cut up and melted down at steel works where they blended in with other scrap metal while the carriages and platforms were dismantled and scrapped. All technical documentation, including blueprints, calculations, and firing reports, was likely destroyed. As for the crews, they were ordered under threat of prosecution to maintain strict secrecy regarding their service on this object.

 The Allied forces managed to secure only a limited number of weapon components. Spare parts, fragments of breach mechanisms, guidance systems, and armor plating were discovered in various locations. At one railway station, three massive platforms were found with a design suggesting they could be used to transport superheavy artillery.

 These platforms were sent to France for engineering analysis. But without the gun itself, specialists couldn’t accurately determine its specifications. Several unused 120 kg shells with matching markings were also seized. Disassembling and studying them provided some insight into the munition’s design, but full data on the artillery system remained out of reach.

 French intelligence continued their search, attempting to make contact with the former personnel who had operated the weapon. During the investigation, agents questioned demobilized soldiers, offering cash rewards for information while also reminding them of potential liability for war crimes related to the shelling of civilian targets.

 A number of individuals agreed to testify, but the information provided turned out to be contradictory and incomplete, making it difficult to verify. Accounts varied. Some sources described a 40 meter long gun housed in a concrete bunker. Others claimed that there were three units firing in rotation, while others mentioned rocket propelled shells.

 It became clear that precise technical details were being concealed and the testimony received was just a mix of hard facts and rumors. In the post-war period, historians and technical experts attempted to reconstruct the weapons parameters based on circumstantial evidence. Analysis of impact craters was conducted, shelflight trajectories were studied, and eyewitness accounts were gathered.

 Experts ran reverse calculations to determine the specifications of a gun capable of delivering a 120 kilogram warhead over a distance of 120 kilometers. The data pointed to extreme technical parameters. A barrel length exceeding 30 meters, incredibly high pressure, and a muzzle velocity of more than 1.5 km/ second. A number of experts expressed doubts about the engineering feasibility of such a system.

 Over time, attention to the Paris gun faded as a new technological era dawned. The development of aviation made it possible to deliver a much larger payload deep into enemy territory. Building expensive and immobile artillery complexes became economically unjustifiable since aircraft could perform similar missions faster and cheaper.

 The concept of ultra long range artillery was deemed a dead end and the weapon itself was relegated to a historical technical oddity with no widespread practical use. Germany’s military leadership did not abandon the concept of superlar caliber guns. During the inter war period, troop engineers continued working on superheavy artillery, utilizing the experience gained from operating the Paris gun.

 New technologies for manufacturing long barrels were introduced. Ballistic trajectory calculations were improved and targeting systems were refined. These developments led to the appearance during World War II of systems such as the 800 mm railway gun Dora and the 600 mm mortar Carl. These models significantly surpassed their predecessors in power, but they retained the characteristic flaws of their class.

High cost, low mobility, short barrel life, and questionable effectiveness. According to some World War I artillery veterans, the Paris gun wasn’t the only super long range weapon in existence. There were reports that Germany had developed additional smaller caliber guns designed to hit other French cities.

 One theory suggests there were plans to deploy an entire battery to systematically shell France’s industrial centers, aiming to disrupt war factories and transportation networks. However, no documentary evidence has ever been found to support this. It is possible these were just unrealized projects or simply widespread wartime rumors with no basis.

In fact,