The site is officially known as "Kuh-e Kolang-e Gaz La," a Persian name meaning "Mount Axe," and is located less than two kilometers south of the Natanz uranium enrichment complex, which was hit by U.S. strikes in 2025. It has been carved into the depths of Iran's Zagros Mountains in a strategically fortified location.

Unprecedented Depth and Exceptional Fortification

The site lies at a depth of up to 600 meters below the surface, making it six times deeper than the Fordow facility, previously considered the most fortified in Iran's nuclear program. It features four main tunnel entrances, complicating any attempt to seal it via airstrikes. U.S. experts believe this depth may place it beyond the reach of the most powerful bunker-buster bombs currently available.

Site Functions According to Intelligence Estimates

Experts expect the facility to house factories for manufacturing next-generation centrifuges, along with intelligence estimates indicating that Iran has moved part of its stockpile of 60% enriched uranium into it. According to specialized analyses, this site could enable Iran to produce up to 19 nuclear weapons within three months.

Trump Watches as Pressure Mounts

U.S. President Donald Trump confirmed that his country is closely monitoring the site, stating: "We are closely watching the Mount Axe site in Iran and see no activity there," adding that "their nuclear situation is not good," and that "every time we hear about something, we destroy it."

Trump is facing mounting pressure from the Jewish Institute for National Security of America (JINSA) to address the site as quickly as possible. Blaise Misztal, the institute's vice president, said: "The Mount Axe site is deeper, larger, and better fortified than Fordow," warning that it may be beyond the range of U.S. bombs. Meanwhile, institute president Michael Makovsky asserted that failing to completely dismantle Iran's nuclear program would be "a major missed opportunity."

Refusal of Inspection and Accelerated Construction

Iran has never allowed the International Atomic Energy Agency to visit the site, leading to what is described as a "blind spot" beyond the reach of international inspectors. Satellite images, including those from Airbus's "Pleiades Neo" satellite, have revealed that Iran accelerated construction at the site following the U.S. strikes, and the images showed trucks suspected of transporting highly enriched uranium into the tunnels.

Why Wasn't the Site Targeted?

The omission of the site from previous strikes is due to a number of factors: its exceptional depth of 600 meters, the natural protection provided by the towering mountain, the multiple (four) tunnel entrances that complicate sealing it via bombardment, and the lack of precise intelligence on its current contents. U.S. experts stress that the site represents a fundamental gap in any claim of completely destroying Iran's nuclear program.