Find out which famous person was secretly kept in the castle to work on a project that would change the world.
Of course, little Rudi was at the scene to sniff it all out and came to a striking conclusion.
The collectible letter is printed on quality 250gr cardstock. Included in the mailing is an art postcard of the castle, a matching sticker, a cancelled German postage stamp, a bookmark and a surprise.
As an extra touch of faraway Germany, the contents are wrapped in a piece of a real local German newspaper.
