A cyclone for a surface cleaning apparatus has spaced apart and opposed first and second cyclone chamber end walls and a cyclone chamber sidewall extending therebetween. At least one of the first cyclone chamber end wall and the second cyclone chamber end wall is openable so as to provide access to the cyclone chamber. An opening extends along only a portion of the perimeter of the cyclone chamber sidewall and is positioned adjacent the second cyclone chamber end wall, the opening defining the dirt outlet whereby dirt exiting the cyclone chamber via the dirt outlet travels in a generally outwardly direction to an exterior dirt collection chamber.