- CSIS analysis shows significant surge in road and construction activity at Pickaxe Mountain in 2026, more than any prior period.
- Upgrades include portal hardening, internal road paving, access reinforcement, and removal of excavation spoil around the underground entrances.
- Analysts could not confirm Israeli claims that centrifuges were moved into the site, leaving military intent unresolved.
- IAEA has requested information and access to Pickaxe Mountain; Iran has reportedly not responded to those requests.
- The granite fortification is described as deeply buried and hard to destroy even with heavy non nuclear US munitions.
A suspected underground Iranian nuclear site has seen a surge in construction this year, according to a review of satellite imagery published by US analysts on Wednesday.
The deeply buried site at Pickaxe Mountain is near Natanz where Western intelligence suspects Iran is building an undeclared enrichment facility.
On July 21, President Donald Trump threatened a US military strike on Pickaxe Mountain in his war against Iran that has the declared aim of destroying its nuclear program.
Analysts at the Center for Strategic and International Studies (CSIS), a Washington-based think tank, reviewed satellite imagery spanning six years, the latest from August 9.
“Together, these images reveal more road activity at Pickaxe Mountain in 2026 than at any point in the site’s history,” the CSIS analysts wrote.
“There is a clear surge in construction activity in 2026 that corresponds to the raising and hardening of the portal accesses, paving of the internal road network, reinforcement around access areas, and the flattening and removal of excavation spoil,” they added.
However, the analysts added that they could not refute nor substantiate a reported Israeli intelligence claim that Iran moved centrifuges into Pickaxe Mountain.
In July, Trump said, “We’ll be hitting that area pretty soon, and very heavily,” but apparently did not follow through on the threat.
The International Atomic Energy Agency (IAEA), the UN nuclear watchdog, has requested information about Pickaxe Mountain and access to the facility. Iran has reportedly never responded to the IAEA requests, CSIS said.
The deeply buried granite fortification would be difficult to destroy even with the heaviest non-nuclear US munitions, the analysts wrote.
The US-Iran war is in its seventh month. On Wednesday, Iran launched fresh attacks against US targets in the Middle East in retaliation for American strikes on Iranian oil tankers, dragging the foes deeper into armed conflict.
