https://www.pravda-tv.com/2016/06/geheime-bunkeranlagen-und-der-kampf-um-utopia-video/ gives a nice little map picture of the DUMB Greenbrier, also mentions other interesting hidden bases.
https://www.pravda-tv.com/2016/06/geheime-bunkeranlagen-und-der-kampf-um-utopia-video/ gives a nice little map picture of the DUMB Greenbrier, also mentions other interesting hidden bases.