U.S. Military Unleashes the GBU-57 on Iran’s “Pickaxe Mountain” Nuclear Site — What Happened Next Stunned the World

U.S. Military Could Unleash the GBU-57 on Iran’s “Pickaxe Mountain” Nuclear Site — What Happens Next Could Reshape the War

A remote mountain rising above Iran’s central plateau has suddenly become the focus of one of the most dangerous military confrontations in the Middle East.

Known internationally as “Pickaxe Mountain,” the heavily fortified site near Iran’s Natanz nuclear complex is believed to conceal an expanding network of tunnels, protected chambers, and underground facilities buried beneath hundreds of feet of rock. For years, Iranian engineers appear to have worked on the assumption that the mountain’s depth and geology would shield the complex from even the most powerful conventional weapons in the American arsenal.

That assumption may soon face its greatest test.

President Donald Trump has publicly identified the area as a potential American target, declaring that the United States could strike it “pretty soon” and “very heavily.” Iran’s military leadership answered within approximately 24 hours, warning that an attack on the mountain would represent a major expansion of the regional war and trigger retaliation against American interests, allies, and supporters.

The exchange has transformed Pickaxe Mountain from a secretive construction project into a public red line.

At the center of the confrontation is the GBU-57 Massive Ordnance Penetrator, the largest conventional bunker-busting bomb deployed by the United States. Weighing roughly 30,000 pounds, the weapon was developed to strike deeply buried military installations that ordinary bombs cannot reach.

Yet Pickaxe Mountain may present a challenge unlike anything the GBU-57 has previously faced.

The facility is believed to lie at least 100 meters beneath the surface, surrounded by solid granite and possibly protected by multiple tunnel systems. That depth exceeds commonly cited estimates for the GBU-57’s direct penetration capability, raising an uncomfortable question for American military planners: can the most powerful conventional bunker-buster in the world actually destroy what Iran has hidden inside the mountain?

The answer could determine not only the future of Iran’s nuclear infrastructure, but also whether the confrontation expands into a far wider regional conflict.

A Mountain Built in Response to Destruction

Pickaxe Mountain did not emerge from nowhere.

The site, known in Iran as Kuh-e Kolang Gaz La, sits approximately one mile south of the Natanz uranium enrichment complex. Natanz has long been one of the most important locations associated with Iran’s nuclear program and has repeatedly been targeted by sabotage, cyber operations, and military strikes.

Construction on the mountain complex reportedly began around 2020, after an above-ground centrifuge assembly building at Natanz was destroyed. The incident was widely attributed to Israeli sabotage, although the full details were never publicly confirmed.

Iran subsequently informed the International Atomic Energy Agency that it planned to build a replacement facility underground. According to outside assessments, the new complex was intended to support the production or assembly of thousands of centrifuges each year.

Centrifuges are essential to uranium enrichment. By spinning uranium gas at extremely high speeds, they gradually increase the concentration of the uranium-235 isotope. Low-enriched uranium can be used for civilian nuclear energy, while material enriched to higher levels can bring a country significantly closer to the technical threshold required for a nuclear weapon.

Iran has consistently insisted that its nuclear activities are peaceful. Western governments and Israel, however, have argued that the scale of Iran’s enrichment program, its advanced centrifuges, and its accumulation of highly enriched material create an unacceptable weapons risk.

The destruction of the earlier centrifuge facility appears to have reinforced a lesson already understood by Iranian planners: anything built above ground could be located and destroyed.

The answer was to go deeper.

Satellite images studied by independent analysts revealed excavation work, road development, spoil piles, tunnel entrances, security fencing, and defensive construction around the mountain. The wider complex is believed to cover several square kilometers of dry, rugged terrain.

The site’s elevation and surrounding geology add another layer of protection. Analysts have estimated that parts of the underground facility may sit at least 100 meters, or approximately 328 feet, beneath the surface.

More recent imagery has led some experts to suggest that the deepest chambers may be located even farther underground.

If those estimates are accurate, Iran has constructed a facility deeper than the commonly reported penetration limit of America’s most powerful conventional bomb.

Why Pickaxe Mountain Became More Important After 2025

The strategic importance of Pickaxe Mountain reportedly increased dramatically following the attacks on Iran’s other major nuclear facilities in June 2025.

During that campaign, American and Israeli forces struck sites associated with Iran’s nuclear program, including Natanz, Isfahan, and Fordow. The operation reportedly involved extensive air attacks and the first combat use of the GBU-57 Massive Ordnance Penetrator.

Fourteen GBU-57 bombs were reportedly deployed across the targeted facilities.

Fordow was considered an especially difficult target because it had been built deep inside a mountain. The facility’s position had long complicated military planning and created uncertainty about whether conventional weapons could destroy its underground halls.

The GBU-57 was developed for precisely this kind of mission.

After the attacks, however, attention shifted toward the facility near Pickaxe Mountain—the major underground complex that had not been struck.

Rather than slowing construction, Iran appeared to accelerate efforts around the site. Satellite analysis reportedly showed new walls, expanded security measures, continued excavation, and the development of multiple tunnel entrances leading into different sections of the mountain.

Tunnels were identified on the eastern, western, and southern sides of the complex.

Such activity suggested that Iran was not abandoning the project. Instead, Tehran appeared to be strengthening the one major facility that had survived the earlier campaign.

According to reporting cited in the source material, Israeli and American officials believe Iran later transferred thousands of centrifuges into the underground chambers. The equipment was reportedly moved during the months following the 2025 conflict.

The centrifuges alone would not constitute an active nuclear weapons program. They would require uranium feed material, operating infrastructure, power, trained personnel, and a functioning cascade configuration.

Nevertheless, protecting thousands of centrifuges would preserve Iran’s ability to rebuild enrichment capacity more rapidly in the future.

That possibility appears to be driving Washington’s interest in the mountain.

Trump Publicly Names the Target

Military leaders normally avoid revealing detailed plans before an operation. Publicly identifying a target could give an adversary time to relocate equipment, reinforce defenses, prepare air-defense systems, or organize retaliation.

Trump’s comments therefore attracted immediate attention.

During an earlier media appearance, he said the United States was watching Pickaxe Mountain closely. He suggested that whenever Washington detected renewed Iranian nuclear activity, it was prepared to destroy it.

His language became more direct during an Oval Office appearance beside Lebanese President Joseph Aoun.

Trump told reporters that the United States would be hitting the area “pretty soon” and “very heavily.” He then claimed there was nothing Iran could do to stop it.

Even more significantly, Trump explained why he was willing to discuss the target publicly. He suggested he would not reveal the plan if he believed Iran possessed the ability to prevent the operation or respond effectively.

The statement conveyed extraordinary confidence.

It also created strategic pressure.

By naming the mountain, Trump placed Iran’s leadership in a difficult position. If Tehran removed equipment from the complex, the movement could be detected by American or Israeli surveillance. If it left the equipment in place, it risked losing valuable centrifuges and infrastructure in an attack. If it responded by activating the site, it could give Washington a stronger justification for military action.

The comments could therefore be interpreted as psychological warfare as much as an operational warning.

Repeatedly declaring that a strike is coming can force an adversary to spend resources, disperse forces, place units on alert, and prepare for an attack that may occur at any moment.

However, such threats also create political pressure on the country issuing them.

Once an American president publicly promises a major strike, repeatedly delaying the operation could make the threat appear less credible. The phrase “pretty soon” can function as pressure for a limited period, but eventually observers begin to expect either military action or a diplomatic breakthrough.

Iran Warns of a Wider War

Iran’s response was rapid and unusually direct.

The country’s Khatam al-Anbiya Central Headquarters, a senior military command structure, warned that an American attack on Pickaxe Mountain would amount to an expansion or “explosion” of the regional war.

The statement reportedly threatened a powerful response against American interests and against nations supporting Washington.

This language matters because Iran did not describe the potential attack as merely another isolated bombing raid. It presented the strike as a threshold event that could justify a much broader military reaction.

Iran possesses several possible methods of retaliation.

It could launch ballistic missiles or drones against American military bases in the region. It could target facilities used by U.S. allies. It could increase pressure on shipping near the Strait of Hormuz, one of the world’s most important energy corridors. It could also rely on allied armed groups to carry out attacks in other countries.

The United States has repeatedly attempted to weaken these capabilities through attacks on Iranian command centers, drone storage sites, air defenses, and logistics networks.

Trump’s confidence appears to rest partly on the belief that those operations have reduced Iran’s ability to respond.

Tehran is determined to prove otherwise.

The competing statements have created a dangerous credibility contest. Washington claims Iran cannot stop the attack or impose an acceptable cost afterward. Iran claims any attack will produce a powerful regional response.

If either side miscalculates the other’s capabilities or political intentions, escalation could occur rapidly.

What the GBU-57 Is Designed to Do

The GBU-57 Massive Ordnance Penetrator is unlike ordinary aerial bombs.

The weapon is approximately 20 feet long and weighs around 30,000 pounds. Much of that weight comes from its hardened metal casing, which allows the bomb to survive the enormous impact forces created when it strikes rock or reinforced concrete at high speed.

Rather than exploding immediately on the surface, the GBU-57 is designed to penetrate underground before detonating.

The delayed explosion transfers destructive energy into the surrounding earth and structures. Even when the bomb does not strike a chamber directly, the resulting shock wave can collapse tunnels, destroy internal equipment, cut power lines, block entrances, and damage ventilation systems.

The B-2 Spirit stealth bomber is the only operational American aircraft publicly known to carry the weapon.

The B-2’s low-observable design allows it to approach heavily defended targets with a reduced risk of detection. Its long range also enables missions launched from distant bases, supported by aerial refueling and extensive intelligence operations.

A strike on Pickaxe Mountain would likely require far more than simply releasing one bomb over a set of coordinates.

American forces would first need to suppress or evade Iranian air defenses. Intelligence teams would need to identify the most vulnerable points in the tunnel network. Mission planners would need detailed information about the geology, internal layout, access shafts, ventilation systems, power sources, and probable location of critical equipment.

Even minor targeting errors could significantly reduce the weapon’s effectiveness.

Against a normal surface target, a miss of several meters might still produce severe damage. Against a narrow underground tunnel or access shaft, the same error could mean the bomb strikes solid rock while the most important chambers survive.

The Depth Problem

The central technical issue is depth.

Older U.S. Air Force assessments have suggested the GBU-57 was designed to penetrate up to approximately 200 feet underground under certain conditions. Its performance depends heavily on the material it strikes.

Soil, concrete, fractured rock, and solid granite do not behave in the same way.

Pickaxe Mountain’s underground complex is estimated to lie at least 328 feet beneath the surface. If the deepest halls are located directly below that amount of granite, a single GBU-57 may not be capable of physically reaching them.

That does not necessarily mean the facility is safe.

The goal of a strike does not always require the bomb itself to enter the main chamber. Destroying tunnel portals, collapsing access routes, cutting electricity, damaging ventilation, and trapping equipment underground could render the facility unusable for months or years.

The United States could also use sequential strikes.

Under this approach, one bomb creates an initial crater. A second bomb is then guided toward the same impact point, using the damaged area to penetrate farther. Additional weapons could repeat the process.

This “one-two punch” concept has reportedly been discussed in connection with previous attacks on deeply buried facilities.

Executing it would be extremely difficult.

Each bomb would need to strike nearly the same location. Dust, smoke, debris, shifting rock, and changes to the crater could complicate guidance. The aircraft might need to conduct multiple passes, increasing the duration and risk of the mission.

Iran could also attempt to interfere through electronic warfare, air-defense fire, decoy construction, or rapid repairs.

Even a technically successful sequence might not guarantee the destruction of every underground hall.

Granite Could Change Everything

The geology surrounding Pickaxe Mountain may be one of Iran’s strongest defenses.

Solid granite is dense, strong, and resistant to penetration. A weapon entering the mountain at high speed would experience extreme mechanical stress. The harder the rock, the more energy the bomb loses before reaching its intended detonation point.

Some analysts have warned that the GBU-57’s performance at Fordow cannot automatically be used to predict its performance at Pickaxe Mountain.

Fordow and Pickaxe Mountain may contain different types of rock, tunnel designs, reinforcement systems, depths, and internal layouts.

Iranian engineers also had the opportunity to study previous attacks.

If they understood how American forces targeted Fordow—whether through direct penetration, tunnel entrances, ventilation shafts, or other structural weaknesses—they could design the newer facility to eliminate similar vulnerabilities.

Access tunnels may curve rather than run in straight lines. Blast doors may divide the underground complex into separate sections. Critical equipment may be placed away from entrances and ventilation shafts. Redundant power and air systems could allow some sections to continue operating after others are damaged.

This does not make the facility indestructible.

It makes the result less certain.

The Missing Uranium Question

Trump has emphasized that centrifuges are not the only issue. The enriched uranium itself is more important.

Before the 2025 strikes, Iran had produced uranium enriched to approximately 60 percent purity. That level is significantly above what is normally required for civilian nuclear power and much closer to weapons-grade material.

Trump told reporters that the United States was following the nuclear material.

His distinction is strategically important.

Thousands of centrifuges stored underground would give Iran a future capability. A stockpile of highly enriched uranium could create a more immediate proliferation concern.

According to the source material, the existing stockpile was believed to remain connected to previously targeted nuclear sites rather than Pickaxe Mountain. Iran was not publicly known to have restarted large-scale enrichment inside the mountain.

But the lack of international access makes certainty impossible.

The International Atomic Energy Agency has reportedly never inspected the underground Pickaxe Mountain facility. Outside governments and independent experts are therefore relying heavily on satellite imagery, intelligence assessments, construction patterns, and indirect evidence.

Iran’s Foreign Ministry has said that the country declared its nuclear activities and that no nuclear work was occurring inside the mountain.

Without inspections, that claim cannot be independently verified.

The same problem applies to Western allegations. Officials may possess classified intelligence, but the public cannot evaluate the full evidence.

This information gap increases the risk of war.

One side sees a protected centrifuge complex that could help rebuild Iran’s enrichment program. The other says the facility contains no active nuclear operation. Neither position can be conclusively tested without access.

Could Diplomacy Still Prevent the Strike?

A diplomatic path technically remains available.

Iran could allow international inspectors limited access to the site, provide documentation concerning the centrifuges, or agree to monitored restrictions on the use of the facility.

Such measures could reduce uncertainty and make an immediate American attack less likely.

However, Tehran may view inspections as a security threat. Revealing the layout of tunnels, entrances, equipment halls, or protective systems could provide valuable targeting information to the United States or Israel.

Iran may also believe that allowing access under military pressure would appear to be a humiliating surrender.

Washington faces its own constraints.

After publicly threatening a heavy strike, the administration would need to present any diplomatic agreement as a meaningful Iranian concession. A limited inspection that leaves major questions unanswered might not satisfy American or Israeli officials.

Diplomacy therefore requires both sides to accept political risk.

Iran would need to reveal information about a highly sensitive facility. The United States would need to delay military action and trust an inspection process that might be incomplete.

As military operations continue elsewhere, the opportunity for such an agreement may be narrowing.

What a Strike Could Achieve

A successful attack might destroy stored centrifuges, collapse tunnels, damage assembly halls, and delay Iran’s ability to restore enrichment.

It could also demonstrate that no underground facility is beyond the reach of the United States.

That psychological effect may be as important as the physical damage.

Iran’s nuclear strategy has increasingly relied on dispersion, concealment, and depth. If Pickaxe Mountain were rendered unusable, Tehran would be forced to reconsider whether building deeper facilities can provide lasting protection.

However, military action could also produce unintended consequences.

Iran might conclude that negotiated limits offer no security and that only an actual nuclear deterrent can prevent future attacks. The government could withdraw further from international monitoring, disperse its remaining equipment, or accelerate secret nuclear work at smaller unknown locations.

A strike could destroy infrastructure while strengthening Iran’s determination to rebuild.

It could also trigger the retaliation Tehran has promised.

American bases, allied territory, commercial shipping, and regional energy infrastructure could all face increased danger. Insurance costs and oil prices could rise sharply. Civilian air travel and maritime transport could be disrupted.

The military success of bombing one mountain would not automatically prevent a broader strategic crisis.

What Happens if the Bombs Fail?

Failure would carry serious consequences.

If the United States used multiple GBU-57 bombs but failed to destroy the deepest sections of Pickaxe Mountain, Iran could claim that its underground strategy had defeated the most powerful conventional weapon in the American arsenal.

Even if entrances were damaged, Tehran might eventually excavate new routes and recover surviving equipment.

A partially successful strike could be especially problematic. Washington might know the facility was damaged but remain uncertain about what survived. This could lead to repeated attacks, continuing surveillance, and pressure for follow-up operations.

Iran, meanwhile, could use the uncertainty to its advantage.

It could claim the complex remained operational even if it was severely damaged, or claim it had been destroyed while secretly rebuilding elsewhere.

The fog surrounding underground warfare makes definitive victory difficult to prove.

Satellite images can reveal collapsed entrances, craters, ground movement, and reconstruction. They cannot always show the condition of chambers hundreds of feet below the surface.

The World Is Watching One Mountain

Pickaxe Mountain now represents more than a nuclear facility.

For Iran, it is a symbol of survival, technological resilience, and the belief that national infrastructure can be protected through secrecy and depth.

For the United States, it is a test of military reach and political credibility.

For Israel, it may represent the most important remaining node in Iran’s ability to rebuild sensitive nuclear capabilities.

For the wider region, it is a potential trigger for another major escalation.

The confrontation is particularly dangerous because both sides have made public commitments.

Trump has repeatedly suggested that a powerful strike is approaching. Iran’s military command has publicly promised severe retaliation if it occurs.

Backing away now would require an agreement, a change in intelligence, or a political decision that one side is willing to absorb accusations of weakness.

Moving forward risks an unpredictable war.

A Threat, Not Yet a Confirmed Attack

Despite the dramatic headlines surrounding the GBU-57 and Pickaxe Mountain, the most important fact remains that no confirmed strike was described in the source material.

The situation is a rapidly escalating threat.

Pickaxe Mountain is real. The construction activity around it has been extensively observed. The facility is believed to be deeply buried, heavily protected, and potentially connected to Iran’s centrifuge program.

The GBU-57 is also real. It is the most powerful conventional bunker-penetrating weapon in the United States inventory and has been developed for targets of this kind.

Trump’s threats were direct. Iran’s warning was equally clear.

What remains unknown is whether the United States will carry out the strike, what intelligence would trigger the final order, how many weapons would be used, and whether the deepest chambers could survive.

The mountain may delay an attack. It may complicate targeting. It may reduce the likelihood that a single mission completely destroys the complex.

But it has not kept the facility hidden.

American and Israeli officials appear to know where it is, how construction has progressed, and what equipment may have been transferred there. The site’s secrecy has already been compromised, even if its physical defenses remain formidable.

The decisive question is therefore no longer whether Pickaxe Mountain can be found.

It is whether it can be destroyed without igniting a much larger war.

As bombers, missile units, surveillance aircraft, satellites, and military commands remain on alert, the confrontation has entered a stage where language itself is becoming dangerous. Every new warning reduces the political space for compromise. Every public threat raises expectations that action will follow.

Iran built Pickaxe Mountain because previous facilities proved vulnerable.

The United States developed the GBU-57 because some targets were considered too deep for ordinary weapons.

Now those two strategies may be approaching a direct collision.

If American bombers are eventually ordered toward the mountain, the operation will test the limits of precision warfare, underground engineering, intelligence collection, and conventional firepower. It will also test whether either side can control the escalation that follows.

The bombs may be capable of breaking rock.

Whether they can break the cycle of retaliation—or prevent the conflict from spreading far beyond the mountain—is another question entirely.