It is known as `` Gate Night '' in Trail , British Columbia , Winnipeg , Canada and as Mat Night in Quebec , Canada , always on the 30 October , the eve of Halloween . It is known as `` Gate Night '' in Trail , British Columbia , Winnipeg , Manitoba , Thunder Bay , Ontario , Rockland County , NY , North Dakota and South Dakota ( USA ) and as `` Mat Night '' in Quebec , Canada , always on the 30 October , the eve of Halloween .