Clockarium is a small museum devoted to Art Deco ceramic clocks, the colourful mantel clocks that were common in Belgian and northern French homes in the early 20th century. The collection fills several floors, with Belgian, French, Czech, German, Dutch, Austrian, and Italian examples.
The building is part of the appeal: an Art Deco house designed by Gustave Bussuyt. It is a niche stop, but a memorable one for visitors interested in design history. Opening times are limited and tours are generally in French, so check ahead.