I think it's the Wolf's Lair in East Prussia. I'd love to visit it - is there much to see?
a) you are right! ✔️
b) It's worth a 2-3 hours visit, but there's not too much of infrastructure there. I had the impression they try to keep things on a low level not to attract to many Nazis. Nevertheless an impressive place and most of the tour is a free walk.
It was Hitler's headquarters in Poland, the Wolf's Lair near Ketrzyn in Gierloz. This is the site of Stauffenberg's assassination attempt, which failed.
The bunkers were blown up by the Wehrmacht at the retreat. Not all of them could be destroyed because they were simply too massive.
edit: They have multilingual information boards there
![[Linked Image]](https://up.picr.de/41119225mp.jpeg)
If you are interested in a real impressive WWII location I would recommend Wolgograd/Stalingrad in Russia. I was there repeatedly during Soviet times. The Russians know how to present things related to The Great Patriotic War.