Iran Is Believed To Have Nuclear Facilities Deep Inside a Mountain. Analysts Say Construction Is Increasing There.

Analysts say construction activity has increased at a suspected Iranian nuclear site buried deep inside a mountain. (Credit: Getty Images)

A suspected Iranian nuclear facility buried deep inside a mountain is seeing a "clear surge in construction activity" this year, experts are saying.

The site in question is known as Pickaxe mountain and is located near the Natanz nuclear complex, which was bombed by the U.S. last year during Iran's 12-day war with Israel. It hosts two tunnel complexes experts believe can't be reached by the U.S.'s most powerful bunker buster bombs.