For years I walked by this place wondering what it was. Recently, I decided to check it out and it turns out to be a really nice garden that belongs to the Raad van State, which is a part of the Dutch government and it is freely accessible during opening hours. The building used to be the palace of the King of The Netherlands and the building next to the garden, the Gothic Hall, used to be a gallery for the collection of paintings owned by the King.
It is quite small but feels like a little sanctuary in the middle of the city center. The garden is filled with different statues. I love to look at art and wonder what the meaning behind a piece is and this is a nice place to do just that. There is also some kind of poem made of neon lights that hangs on the building surrounding the garden. This is a really nice place to stop by during a walk through the city center and see how old architecture and modern art interact with one another.