Iran's nuclear fortress beneath Kolang Gaz La mountain

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The impact of the 12-day war between Tel Aviv and Tehran on Iran's nuclear facilities is far from clear, between the US administration's assurances that "everything was destroyed" and the reports that the attacks only set Iran back a few months. What is certain is that a complex, hidden deep in the Kolang Gaz La mountain and still under construction, emerged unscathed. It is just a few minutes away from the Natanz plant and is being excavated deeper than Fordow, considered the 'crown jewel' of Iran's uranium enrichment programme.

It is not known when Iran began building the nuclear facilities beneath Kolang Gaz La, also known as 'Pickaxe' Mountain. Work on the complex was made public in 2007 by the Institute For Science And International Security (ISIS). Even less is known about what goes on in its underground tunnels and chambers, which the International Atomic Energy Agency (IAEA) has never been allowed to inspect.

Despite repeated requests for explanations from Iran, the response has always been the same. “Since it is obvious that this is a place where numerous and important activities related to the [nuclear] program are taking place, we are asking them ‘what is this for?’ They are telling us: ‘It is none of your business’,” director Rafael Grossi revealed in April this year. At the time, the official admitted that “it cannot be ruled out” that the tunnels of the complex store material that has not been declared to the United Nations agency.

Iran's nuclear power is buried in a mountain. And for now, only the US has a bomb to destroy it.

Experts have described to the international press that the Kolang Gaz La complex is deeper and better protected than others in the Iranian nuclear program. Just compare it to the Fordow facility, the most important. It is thought to have two entrances, while the Pickaxe Mountain complex has at least four: two to the east, two to the west. As the Financial Times notes, this could make it difficult for enemy forces to block the entrances through bombing.

Furthermore, as The Telegraph reports, the underground chambers were built at greater depths. While the Fordow chambers are around 60 to 90 meters deep, the Kolang Gaz La chambers are estimated to be more than 100 meters deep. “The underground complex at Kolang Gaz Lā or ‘Pickaxe’ mountain is intended to provide the regime with a nuclear weapons site that even the US Air Force would struggle to destroy with its largest conventional bombs,” researcher Reuel Marc Gerecht of the think tank Foundation for Defense of Democracies (FDD) told the British newspaper.

Some experts fear the facility could be used to build a nuclear weapon. “A key question is whether Iran will, or perhaps has already, secretly placed fissile material at Pickaxe or some other unknown facility,” Ben Taleblu, also from the FDD, told the Financial Times.

In April this year, the Institute For Science And International Security reported that a new security perimeter had been detected around Kolang Gaz La, something that raised new concerns for experts. Speaking to Reuters , David Albright, president of the institute, acknowledged that this is a sign that the tunnel complexes could become operational soon.

According to a June 24 report by the institute, written by David Albright and Spencer Faragasso, “no damage was observed in satellite images of the complex being built under Mount Kolang Gaz La.” The potential for Iran is huge, the organization believes. “This facility will house an advanced centrifuge assembly unit and could house the new centrifuge enrichment plant that Iran has said it wants to open soon,” read another analysis, dated June 13.