The Eagle’s Nest
So says Wikipedia:
The Kehlsteinhaus (in English-speaking countries also known as the Eagle’s Nest) is a chalet-style structure erected on a subpeak of the Hoher Göll known as the Kehlstein. It was built as an extension of the Obersalzberg complex erected in the mountains above Berchtesgaden. The Kehlsteinhaus was intended as a 50th birthday present for Adolf Hitler to serve as a retreat, and a place for him to entertain visiting dignitaries.