Not far away from the city center and the EU District but no tourists and no EU officials...only a hidden small square away from chaos and among small buildings and nice bar/restaurants which make you feel part of Brussels daily life...
Nothing special to see as somebody else has already said but...interesting atmosphere "to breathe"!
Not much to say about this place, I think it is not among on the major attractions list of the city, nor did not see many tourists here. There's a few bars, some meeting place but nothing worth going specifically to see this attraction.
A good choice in the area to hang out, about 5 minutes walk away from the Park. The square seem to feature some nice bars. You can find some good restaurant on Rue de l'Enseignement, opening from the same square.