An automated warehouse includes first and second stacked racks parallel to each other; first and second shipping-and-receiving stations placed at the same end of the stacked racks; transfer shuttles located between the stacked racks and between the shipping-and-receiving stations; elevator mechanisms equipped with first and second elevator platforms for receiving or transferring the packages to stand-by conveyors; and means for transferring the packages to and from the first and the second elevator platforms. The direction of motion of the stand-by conveyor of the first shipping-and-receiving station and the direction of the motion of the stand-by conveyor of the second shipping-and-receiving station, on the same level of stack, may be opposite; and the direction of motion of some of the stand-by conveyors pertaining to the first shipping-and-receiving station may be opposite to that of the rest of the stand-by conveyors of the first shipping-and-receiving station.