Satellite Images Reveal Ongoing Suspicious Activity at Iran's Secret Nuclear Site

New satellite images from late June 2026 show continued unusual activity at Iran's "Pickaxe Mountain" nuclear facility near Natanz, raising concerns about Tehran's compliance with its nuclear commitments under the memorandum of understanding with the United States. Analysis by the Institute for Science and International Security (ISIS) indicates ongoing construction and reinforcement work at the western tunnel entrances, with vehicle movements detected on access roads. This activity may violate the agreement, which requires Iran to maintain the status quo and prohibits construction at any nuclear-related site, including this mysterious underground complex.

The eastern tunnel entrances remain partially covered with earth, restricting vehicle access, a condition unchanged since early May. ISIS suggests this earth covering is intended to slow vehicle movement rather than completely block access. Meanwhile, other major Iranian nuclear sites, including Natanz and Fordow, show minimal activity and no significant repairs to damaged entrances or restoration of critical systems like cooling and power supply.

The Pickaxe Mountain site, located near the Natanz enrichment facility, is shrouded in secrecy and has never been inspected by International Atomic Energy Agency (IAEA) inspectors. It is believed to be a deeply buried underground complex possibly used for sensitive nuclear activities, storage of materials, or protection against airstrikes. Unlike other Iranian nuclear sites, it has not been targeted in recent attacks attributed to Israel or the US.

Satellite imagery from earlier in 2026 showed partial blocking of tunnel entrances with earth, a change from April when the tunnels were fully open. The ongoing construction and reinforcement efforts at Pickaxe Mountain have drawn increased international scrutiny due to the site's unclear purpose and potential role in Iran's nuclear program. The situation underscores persistent tensions over Iran's nuclear activities and the challenges in monitoring compliance with international agreements.