Considering the Exclusive Hermitage Gantois in Lille?
A VT member wrote the following comment about visiting Lille:
La Vieille Bourse by Mahieu
La Vieille Bourse ( the old Stock Exchange) was built in the 17th century and is a great example of the Flemish Renaissance Style. The building is divided into 24 small commercial houses around a courtyard. You can have a look at the booksellors in the courtyard every afternoon. ( see shopping tip)