This place reminds me of a game I used to play on my computer: Myst.
You are alone, you have to find out where you are...
Is there a key for the bunker? How do you get to the tower?
What will you see up there? What will you find in the bunker???
I loved this game!
Anyway, back to reality, this is the entrance to a bunker an the tower of a mountain airport in Switzerland.
By the way, it was freezing cold there... ;-)