Den Haag (the Hague) has a museum dedicated to Escher, in a palace where Queen Emma (the current king's great-grandmother) lived for much of her life. The palace is mostly empty now, except for these amazing chandeliers in all shapes.
|This one was my favorite!|
And in case you don't know Escher, here's one of his woodblock prints.
The top floor of the palace was dedicated to all the fun and interactive stuff.