Iran Accelerates Construction at Underground Nuclear Site, Satellite Analysis Shows
Iran has significantly increased construction activity at its underground nuclear facility at Parchin this year, according to a new analysis of satellite imagery by the Center for Strategic and International Studies (CSIS). The findings, first reported by CNN, suggest that Iran may be using the site as a secure location for its nuclear program.
The CSIS report identified three phases of development at Parchin. From 2020 to April 2024, heavy construction was evident. Between April 2024 and January 2026, satellite images showed a slower pace of activity. Since January 2026, construction has intensified, though without significant new excavations.
The research institute clarified that its analysis neither confirms nor denies Israeli intelligence claims that Iran has transferred centrifuges to the site. Parchin, located about two kilometers south of the Natanz nuclear facility, is known for its hard rock composition, making it difficult to excavate and potentially challenging for U.S. bunker-buster bombs to destroy.
According to the CNN report, the United States initiated an underground test before the recent conflict to develop methods for attacking deeply buried Iranian underground facilities. Former President Donald Trump recently threatened that the U.S. might attack Parchin "very soon."
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