One of the primary U.S. laboratories focused on the Islamic Republic’s nuclear program has raised concerns about undisclosed underground facilities located in the Zagros Mountains. The International Atomic Energy Agency (IAEA) inspectors currently don’t have access to a secret base known as Pickaxe Mountain.
This heavily fortified site brings up serious doubts regarding Iran’s adherence to the memorandum of understanding (MOU) it negotiated with the Trump administration. A joint operation called Epic Fury was initiated by the United States and Israel on February 28, 2026, aiming at Iran’s nuclear and missile capabilities.
Experts at the Washington-based Institute for Science and International Security (ISIS) suggest that pausing construction at Pickaxe Mountain and extending IAEA access would demonstrate Iran’s willingness to change its historically deceptive practices.
Spencer Faragasso, a senior fellow at the institute focusing on Iran and related issues, recently expressed via social media: “The ongoing construction at Pickaxe Mountain is alarming. This activity has been consistent since at least 2020. It seems to me that Iran is preparing for a backup plan if negotiations fall through, potentially establishing a nuclear facility that is already partially built.” He estimated that the site could be substantial enough to support an enrichment plant.
Iran has previously utilized facilities such as Natanz, Fordow, and Isfahan for uranium enrichment, crucial for its nuclear weapons ambitions. Faragasso noted, “If Iran is genuinely interested in negotiations, it should halt work at Pickaxe Mountain as a sign of goodwill. But given Iran’s history, what can we really expect?”
The institute observed new satellite imagery from late June 2026, indicating ongoing activities at Pickaxe Mountain. They reported that movement was noted on the road leading to the public entrances of the tunnel complex, suggesting continued construction and reinforcement of the site. The MOU stipulates that Iran should maintain the status quo and prohibits further development of nuclear-related facilities, including those at Pickaxe Mountain.
In late June, the IAEA did not provide detailed responses to inquiries about possibly accessing the Pickaxe Mountain facility. Satellite images revealed minimal activity at Natanz, with significant damage to access points. A vehicle was spotted near a damaged enrichment plant that Iran has since protected.
As of late June 2026, the institute also found no activity at Isfahan, where tunnel entrances are still being backfilled. They noted that passive defense measures had been added at Fordow, including earth mounds aimed at slowing vehicle access, possibly indicating preparations for further concealment.
The institute confirmed that recent satellite images show these defenses remain in place, and the tunnel entrances at Fordow continue to be obstructed. Questions were directed to the State Department and Iran’s mission to the United Nations for clarification on these matters.
