Visiting Brussels you should also be looking up all those great Art Nouveau (Jugendstil) houses.
The most famous one is the Horta House.
The wall decorations in Brussels are different from those in Antwerp.
While in Antwerp a lot of mosaic is used, here in Brussels they use wall painting.
Starting from a carved drawing, they put first a top of black colour over it.
And then they put over that one a coloured kind of chalk? and before it totally dries up, they remove the parts that doesn't need to be painted.
This technique they redo over and over again with different colours until the painting is ready.
Fondest memory: Going direction Sint-Gillis where you can find a nice amount of these kind of houses.
Or visiting some of the pubs that are build in Art Nouveau style
See more about Art Nouveau in my travelogues!