An upright vacuum cleaner (A) includes a housing (B) having a suction airstream inlet and a suction airstream outlet. A dirt container (50, 500) is selectively mounted to the housing for receiving and retaining dirt and dust separated from the suction airstream. The suction airstream inlet and the suction airstream outlet are in fluid communication with, respectively, an inlet and an outlet of the dirt container. The dirt container includes a first cyclonic air-flow chamber (66, 508) and a second cyclonic airflow chamber (68, 510), each cyclonic airflow chamber including a longitudinal axis. The second cyclonic airflow chamber is spaced from the first chamber, wherein the first and second chambers are each approximately vertically oriented and are arranged in a parallel relationship. An air manifold (52, 540, 540′) is disposed at a top portion of the dirt container. The air manifold includes an inlet section (54, 536, 565) through which dirty air passes and an outlet section (138, 560, 560′). The inlet section directs a flow of dirty air into two separate inlet conduits leading to a respective one of the first and second airflow chambers. The outlet section collects a flow of cleaned air from both of the chambers and merges the flow of cleaned air into a single outlet conduit (110, 570). An airstream suction source (E) is mounted to the housing and is in communication with the outlet conduit of the manifold.