Iran revealed Fordow's existence on 21 September 2009, touching off an international crisis. President Barack Obama announced that the facility had already been under U.S. surveillance. Western officials condemned Iran for concealing the site; the IAEA stated that Iran was bound by a 2003 agreement to declare any new facility as soon as the decision to build it was made. Iran countered that its obligations only required disclosure 180 days before nuclear material was introduced. The dispute over Fordow's concealment became a defining episode in the breakdown of trust between Iran and the international community. Iran's stated justification for burying the facility inside a mountain was straightforward: repeated Israeli threats to bomb its nuclear infrastructure. The location near Qom added another layer of complexity -- attacking a nuclear facility adjacent to a city sacred to Shia Muslims risked triggering a broader religious backlash.

Fordow was designed to house approximately 3,000 centrifuges across 16 cascades, producing uranium hexafluoride enriched up to 5 percent U-235. In September 2011, Iran announced it would move production of 20 percent low-enriched uranium from the larger Natanz facility to Fordow, and enrichment began in December of that year. The infrastructure was targeted by the Stuxnet computer worm -- a sophisticated cyberweapon widely attributed to the United States and Israel -- which sabotaged centrifuge operations. By March 2023, the IAEA discovered particles enriched to 83.7 percent purity at Fordow, dangerously close to the 90 percent threshold for weapons-grade material. Iran called it an unintentional anomaly. The agency called it a significant surprise.

Under the 2015 Joint Comprehensive Plan of Action, Fordow was to cease uranium enrichment for at least 15 years and be converted into a nuclear physics research center. The facility would retain no more than 1,044 IR-1 centrifuges, with two cascades repurposed for medical isotope production and four left idle. No fissile material was permitted on site. In 2016, Iran deployed S-300 anti-aircraft missiles around the facility as a defensive measure. Then, in May 2018, the United States withdrew from the agreement and reimposed sanctions. By November 2019, Iran announced it would resume enriching uranium to 5 percent at Fordow. The cascade of escalation had begun.

In June 2025, amid the Iran-Israel war, Israeli forces struck Fordow on June 13, though the subterranean enrichment halls, buried deep in the mountain, appeared to survive the initial attack. On June 22, American B-2 Spirit bombers dropped twelve GBU-57A/B Massive Ordnance Penetrators -- the heaviest bunker-busting bombs in the U.S. arsenal -- on Fordow and Natanz, while Tomahawk cruise missiles struck Isfahan. President Trump declared the sites "completely and totally obliterated." Initial U.S. intelligence assessments were less certain, estimating the strikes had set back Iran's program by months rather than years. By September 2025, IAEA Director General Rafael Grossi confirmed that "almost all sensitive equipment" at Fordow had been destroyed. Iran's foreign minister acknowledged the destruction but insisted the country would continue pursuing enrichment as a matter of national pride. Satellite imagery showed Iran building a new access road to the site within days of the strikes.