Joseph Koch’s Fliegendes Museum ? Alive and well apparently, and now in Grossenhain (but was founded in Augsburg, then migrated to the UK before it finally wound up where it is now)

http://www.fliegendes-museum.de/alte_website/Fliegendes_Museum/Flotte.html

Hangar 10 on the Baltic island of Usedom?

http://www.hangar10.de/en/