A nice small gallery, with a lot of book shops.
You get new books or even really old ones. The variety is amazing. But have a look on the prices, as it is not always cheap.
As a tourist or even insider, you should go there.
Galerie Bortiergalerij (Bortiergalerij)
Magdalenastraat 57 Rue de la Madeleine (Magdalenastraat 57), 1000 Brussel, België