39°44'5"N 77°24'50"W Raven Rock complex (site R) is a US. military installation with an underground nuclear bunker holding emergency operations centers for the US Army, Navy, Air Force and Marine Corps.
Located just a few miles from Camp David (the US presidents country retreat), Raven Rock is one of the Pentagon's alternatives.
Planning of this facility started in the early 1950's and in 1955 the automatic activation of Raven Rock's Alternate Joint Communication Center on declaration of air defense warning or notice of surprise attack had been approved. The Site R facility has been regularly modified during the later years.
video footage http://www.youtube.com/watch?v=nAHBekea2Fc
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