... often referred to as "Site R" or just the "Rock" this is an underground alternate command center for the United States Military. Raven Rock Mountain Complex officially houses the Alternate Joint Communications Center (AJCC) and the Alternate National Military Command Center. It is as close as reality comes to the War Room in Dr. Stranglove.
That is- unless you want to speculate about the "Deep Underground Command Center"
and the "Deep Underground Support Center". Both were proposed 1960's super-bunkers. At depths of over 3,000 feet they would have been able to survive a direct hit from a 100 megaton H-bomb! The official story goes that the big-brains in the think-tanks decided that airborne command centers like "Looking Glass" TACAMO and "Nightwatch" were a more survivable and cheaper alternative. The super deep bunkers were canceled. However, it is well known that "Site-R" was additionally hardened in the 1970's to be able to withstand 140psi overpressure. They have built some pretty cool tunneling machines since the 1950's. I would not be surprised if Raven Rock goes a lot deeper than advertised.
all images- Right click- open in New Window= super colossal size!