In Hungary, you can visit the informatics history exhibition with some truly fascinating objects. Did you know the earliest hard case floppy was invented in Hungary in 1973 (!), Wikipedia mentions it too. They have a robot built in 1956-57. It's absolutely fascinating and for us Hungarians really depressing how these never went anywhere due to the Cold War / Iron Curtain.
The address is
Szent-Györgyi Albert Agóra
6722 Szeged, Kálvária sgt. 23 .
Hungary
Szeged is an easy train ride from Budapest.
(I know to some Hungary might not be in the surrounding area of Germany but this is an absolutely unique exhibition. Most of these things you've never heard of and definitely would never ever see anywhere else.)
