Where: Isselburg, Germany
Start of construction: 12th Century
End of construction: 17th Century
Most important renovation: 20th Century
Accessible: yes, interior only with guide
Important fact:
70% of the castle was destroyed at the end of the war in 1945. It was rebuilt afterwards.
Part of the castle contains a museum with more than 700 paintings. Another part is still used as a residence and is not accessible.
http://www.wasserburg-anholt.de/index.php/nl/