In White Sands Missile Test Range. Looks like a radome on the NW end and a mount very similar to this one at the SE end. Same shape and position of the underground entrance.
National Radio Cross Section (RCS) Test Facility
kjfitz
@ 2006-04-22 01:32:16
May be the National Radio Cross Section (RCS) Test Facility of the 46th Test Group at White Sands.
kjfitz
@ 2007-10-02 13:00:31
Now in hi res in GE.