Good evening (here at least),
I never have been to Brussels, so I reached out to a friend who used to travel to NATO HQ often when he was with the US Defense Department. Here are Dave's thoughts for off hours or extended stay wandering.
"There is a nice central "place", a big central square that the old guild houses surround, and just off the plaza is the Mannequin Pis, a statue of a little boy peeing. He has different outfits that he is dressed up in every day. Good shopping for crystal and lace. Really great restaurants on the Rue de Petit Buches (probably spelled wrong - I remember it translated to the Street of Little Butchers). The city speaks French which is kind of strange because it is in the middle of the Flemish part of the country. I think the real attraction would be a side trip over to Bruges. I would really like to get there. It was once a port but silted up centuries ago and therefore got kind of forgotten and locked in time (medieval). Beautiful, with canals and old buildings."