As tensions between Iran and Israel escalate into a broader regional conflict, US President Donald Trump announced on Saturday evening that American forces had carried out successful strikes on three major nuclear sites in Iran — Fordow, Natanz, and Isfahan. These sites form the backbone of Iran’s nuclear infrastructure and have long been viewed by both Israel and the West as critical to Tehran’s potential pathway to developing nuclear weapons.
Here's what we know about each of the targeted locations, why they matter, and why the US likely chose them, according to a CNN report.
Natanz: Iran’s largest uranium enrichment site
- Located about 250 km south of Tehran, the Natanz nuclear facility has been central to Iran’s uranium enrichment programme since it began operations in 2003. Enrichment is a process that increases the concentration of uranium-235 in uranium gas — a necessary step for both civilian nuclear energy and, at higher levels, for nuclear weapons.
- Natanz consists of several above-ground structures and vast underground halls that can reportedly hold up to 50,000 centrifuges. These centrifuges are used to enrich uranium, and recent IAEA reports confirmed that Iran had been enriching uranium at Natanz to 60% purity — close to the 90% level required for a nuclear weapon.
- The site had already been targeted by Israel in April as part of a wider campaign to slow Iran’s nuclear progress. US strikes reportedly followed up by targeting the site’s underground power systems — a critical component, since much of the facility lies deep below the surface. Cutting off electricity is one of the most effective ways to disable centrifuge operations without needing to destroy the underground halls physically.
Fordow: Iran’s most fortified facility
- Hidden deep within a mountain near the holy city of Qom, the Fordow Fuel Enrichment Plant is considered Iran’s most heavily protected nuclear site. First revealed publicly in 2009, the site is located nearly 90 meters underground and was designed to withstand airstrikes. Only the United States possesses the type of bunker-buster munitions capable of reaching that depth.
- Intelligence obtained by Israeli agencies over the years has revealed the plant’s capabilities. According to the Institute for Science and International Security (ISIS), Fordow could convert its stockpile of 60% enriched uranium into over 230 kg of weapons-grade uranium — enough for roughly nine nuclear warheads — in less than a month.
- The IAEA recently reported that Iran had significantly ramped up enrichment activity at Fordow, which now houses approximately 2,700 advanced centrifuges.
3. Isfahan: The research and development hub
- Isfahan, located in central Iran, is home to the Isfahan Nuclear Technology Center — Iran’s largest nuclear research complex. Built in the 1980s with help from China, the facility plays a key role in the early stages of the nuclear fuel cycle.
- According to the Nuclear Threat Initiative (NTI), Isfahan houses three Chinese-supplied research reactors, a uranium conversion facility, a fuel manufacturing plant, a zirconium production plant (used for cladding nuclear fuel), and various laboratories. It employs around 3,000 scientists and is widely considered the intellectual core of Iran’s nuclear programme.
- While Isfahan does not directly enrich uranium to weapons-grade levels, it supports the rest of the program by converting yellowcake (raw uranium) into uranium hexafluoride gas — the form of uranium used in centrifuges at Fordow and Natanz.
Why were these sites chosen?
The three sites struck by the US represent different but interconnected components of Iran’s nuclear capability:
- Natanz is central to high-level uranium enrichment.
- Fordow offers underground resilience and rapid conversion to weapons-grade uranium.
- Isfahan underpins research, fuel production, and conversion, serving as the foundation of the entire programme.
By targeting these facilities, the US aimed not only to degrade Iran’s current capabilities but also to disrupt the infrastructure that allows for long-term development and rapid recovery.
President Trump described the strikes as a “spectacular military success,” stating that Iran’s key enrichment facilities had been “completely and totally obliterated.” However, assessments of the actual damage and Iran’s capacity to rebuild are still ongoing.