Pickaxe Mountain: Iran's Deep Underground Site in Focus
Pickaxe Mountain has returned to the centre of international attention after US President Donald Trump linked the site to a possible strike, even while praising indirect negotiations with Iran in Florida.
Speaking in Florida, Trump welcomed the indirect talks but also said that one or two Iranian nuclear sites remained to be addressed. He specifically named Pickaxe Mountain and said it could be hit very quickly.
The remarks have increased uncertainty over Iran's nuclear programme and American military planning. They also highlight a central puzzle: the site is considered critical, yet much about its current status remains unclear.
Located in Iran's Isfahan province, the site is called Kooh-e Kolang Gaz La locally. Its English name derives from 'kolang', a term connected with a pickaxe or a digging implement.
The mountain lies about two kilometres south of Natanz, one of Iran's main nuclear establishments, and roughly 220 kilometres from Tehran. Inside it is a large set of deep tunnels, with entrances to two separate tunnel complexes.
The key feature of the site is its geology. The tunnels have been excavated within strong granite, which could make the location considerably more resistant to conventional air attacks. Specialists say its depth and natural rock protection could make targeting it extremely challenging.
Concern among Western nuclear experts centres on the site's underground structure and its possible purpose. Some experts think Iran may be developing a uranium enrichment centre here that would be easier to shield from aerial strikes.
Uranium enrichment is the process used to prepare nuclear fuel. Low-enriched uranium can be used in nuclear power plants, while very high enrichment could make weapons development possible.
The United States and Western nations fear that such an underground facility could allow Iran to continue its nuclear activities. Still, it has not been independently established that enrichment is already under way at Pickaxe Mountain.
The Institute for Science and International Security has been tracking the site using satellite images. Its 16 October 2026 report found that soil barriers still block the tunnel entrances, indicating that regular operations and large-scale construction do not appear to be taking place for now.
The report also said the complex might contain important equipment or materials. Media reports from July, which cited Israeli intelligence, claimed Iran had transferred centrifuges and their parts to the site. That claim has not been independently confirmed.
A major reason the mountain draws attention is its protection. The United States possesses powerful bunker-buster bombs such as the GBU-57, designed to strike hardened underground military facilities.
However, analysts note that fully destroying a complex buried deep within a mountain would be difficult. Military action could damage entrances, power supply, ventilation and support structures, but it would not necessarily eliminate every centre inside.
For US planners, the task goes beyond striking the site. They would also need to ensure that any possible nuclear equipment and materials cannot be put to use again.
Pickaxe Mountain has remained relevant even after attacks on other Iranian nuclear locations such as Natanz and Fordow. That is why the Trump administration has continued to describe it as a potential military target.
Iran says its nuclear programme serves peaceful purposes. Western countries, on the other hand, remain doubtful about its uranium enrichment and underground nuclear infrastructure.
Notably, the International Atomic Energy Agency (IAEA) has not inspected this underground complex. As a result, there is no independent confirmation of what equipment is present there or what it is meant to be used for.