Analysts Say Satellite Images Show New Tunnel Hardening at Iran's 'Pickaxe Mountain'; Iran Calls Reports Baseless

Two Ways to Read a Pile of Dirt

Satellite pictures published this month show Iran doing something to a mountain south of Tehran. Everyone agrees on that much. What they don't agree on is what "something" means.

The site is called Pickaxe Mountain in English, Kolang Gaz La in Iran. It sits about 2 kilometers from the Natanz enrichment plant, which was bombed earlier this year, and roughly 220 kilometers south of Tehran ^[2]. Its main chambers are believed to sit at least 100 meters under solid granite ^[2]. Two Washington research groups, using commercial satellite imagery, say Iran spent 2026 reinforcing tunnel entrances, paving roads, and hauling away excavated rock at a pace faster than any of the past six years ^[1]. President Trump has twice this month said the United States might strike it. Iran says there is nothing there to strike.

Both of those things can be true. That's the story.

What the Pictures Actually Show

On Sept. 9, the Center for Strategic and International Studies (CSIS) published an imagery analysis, shared first with CNN, describing a clear surge in construction at the site during 2026 ^[1][3]. It found hardened tunnel portals, newly paved internal roads, and spoil — excavated rock — being removed ^[1]. Two days later, the Institute for Science and International Security published its own update from a Sept. 11 satellite pass. It found that earthen piles blocking access roads since late July remained in place, and that Iran had added more soil over one western tunnel entrance ^[5].

Here is the part that gets lost when these findings travel. Both groups attach a caveat that cuts against the alarm. CSIS says its imagery "can neither confirm nor refute" reports that Iran moved centrifuges inside, and that the nonstop construction actually suggests the site isn't yet capable of enriching uranium ^[1]. The Institute goes further: it says the blocked roads mean Iran can't drive vehicles in at all, which it reads as evidence the facility isn't operating normally right now — even though it believes valuable equipment sits inside ^[5].

So the two firms whose photos are driving the news cycle also say, in their own reports, that the news cycle may be getting ahead of the evidence. That tension is the real story here, more than the photos themselves.

Why a Bunker-Buster Might Not Bust This Bunker

To understand why anyone is talking about airstrikes on a mountain, you need one physical fact. The United States' largest conventional bunker-buster, the GBU-57 Massive Ordnance Penetrator, is reported to punch through about 18 meters of concrete, or about 61 meters of packed earth ^[3][4]. The chambers at Pickaxe Mountain are believed to sit under at least 100 meters of granite — a much harder material than either concrete or earth ^[2]. CSIS says even the GBU-57 might not finish the job ^[3].

That gap is doing a lot of work on both sides. For Washington, it creates urgency: the longer construction continues, the deeper and harder the target gets, and the narrower the window in which a strike could still work ^[3]. Federal contracting records show about $1.2 million spent on urgent work at a granite test facility, evidence that the Pentagon is actively trying to solve the depth problem ^[3]. For Iran, the same physics cuts the other way — burying a program under enough rock is a way to put it out of reach of the one weapon designed to reach it.

Neither side needs to be lying for both of these pressures to be real at once.

No One Has Actually Been Inside

The fact that makes this dispute so hard to settle is an absence, not a presence. IAEA inspectors have never entered the tunnels at Pickaxe Mountain, despite the agency's requests ^[1][10]. That single gap is what lets two opposite stories both sound credible.

Iran can say nothing nuclear happens there, and no photograph from orbit can prove otherwise. The United States can say something does happen there, and doesn't have to prove it either. IAEA Director General Rafael Grossi told Bloomberg Television on Sept. 10 that the agency has observed construction activity using remote imagery — which is, by his own framing, the weakest form of knowledge, and exactly why inspections exist in the first place ^[8].

On Sept. 9, the IAEA's Board of Governors voted to refer Iran to the UN Security Council over nuclear "non-compliance." It's the first such referral in 20 years ^[7]. Sanctions that were lifted under the 2015 nuclear deal have already snapped back into force since September 2025 ^[7]. Iran's ambassador called the resolution driving that referral "one act of lawlessness after another" ^[13].

Three Arguments, Told Straight

The Trump administration's case doesn't rest on any single photo. It rests on the verification gap itself: a country with a purely civilian nuclear program, officials argue, has no reason to bury a site under hundreds of meters of granite and then refuse inspectors ^[1][10]. They also point to a June 17 memorandum in which Iran agreed to hold its nuclear program at the existing status quo — continued construction, in their reading, plainly falls outside that agreement ^[10]. On Sept. 9, Trump told a Republican convention crowd: "We notice there's a little activity at Pickaxe. I would advise Iran not to get cute because we will have to hit them very hard" ^[12].

Iran's government says it's being asked to disprove a negative. Foreign ministry spokesman Esmail Baghaei said on Sept. 14 that all Iranian nuclear activity is declared to the IAEA, and that the focus on Kolang Gaz La — where he says no nuclear work happens — is "a fabricated pretext for aggression, destruction, and sabotage" ^[9][11]. Iranian officials also note they've invited scrutiny rather than blocked it: President Pezeshkian said in September 2025 that satellite pictures can't show what's inside a mountain, and called for inspectors on the ground ^[10]. On the hardening itself, Iran's position is straightforward — a country whose declared, inspected enrichment plants were already bombed has an obvious defensive reason to pile dirt over its doors. That isn't the same thing as enriching uranium ^[5].

The IAEA and the European governments pressing this case — Britain, France, and Germany — frame it differently from Washington. They aren't claiming to know what's inside the mountain. They're claiming they're entitled to look, and have been refused ^[1][10]. Their argument is that a safeguards system means nothing if a state can build an undeclared site and simply decline to answer questions about it ^[7].

How the Same Photos Became Different Headlines

The imagery is identical no matter who's reading it. The framing around it wasn't. Fox News headlines described the site as raising an "urgent threat" that "must be neutralized" — lifting a recommendation into the headline as though it were a finding ^[6][12]. Al Jazeera asked "why now," placing the story inside its running coverage of the broader U.S.-Israel conflict with Iran, and noting that a tanker near Kharg Island was struck hours after Trump's warning ^[2]. CNN's coverage, which got the CSIS study first, spent much of its reporting energy on whether U.S. weapons can even reach the site — shifting the question from what Iran is doing to what America is capable of ^[3]. Arab News, Asharq Al-Awsat, and Al Arabiya largely ran the IAEA's confirmation and Iran's denial side by side, as competing statements ^[8][9][11].

None of that changes the underlying material facts. Construction at the site in 2026 outpaced the previous six years combined ^[1]. No inspector has been inside ^[1][10]. Both of the analyst groups producing the photos say the site probably isn't enriching uranium right now, and neither can say what happens once its doors reopen. One claim circulating in this story — that Iran moved thousands of centrifuges into the mountain — traces back to Israeli intelligence sources and hasn't been confirmed by any of the imagery analyses cited here ^[10].