Wasn't sure whether Halloween was observed/celebrated in Belgium. Certainly didn't see anyone 'trick or treating.' But, there were an awful lot of kiddies dressed in witches outfits, carrying wands. Even some adults. Although they might just have been goths. The strange thing was that on the actual day of Halloween most of the costumes disappeared.
Nevertheless, a lot of the shops in Mons had decorated themselves for the occasion days before and after: fake bits of cobwebs, giant pumpkins, little witch and wizard figures in the windows. Les Montois certainly like to make the most of every kind of event, no matter how small. And good on them for that.