Where: Trechtingshausen, Germany
Start of construction: around 1316/1317
Most important renovation: 19th Century
Accessible: yes
Important fact:
The castle slowly declined in the 16th and 17th century and became a ruin. It was rebuilt
in a romantic way from 1825 to 1844, commissioned by Frederik van Prussia. 
https://www.burg-rheinstein.de/