In a series of experiments,a granular material in a rectangular container with two hollow cylinders was studied as it underwent horizontal vibrations.At the peak values of acceleration,novel swirling granular flows were observed in the cylinders while the grains cascaded down the outer surface of the piles that formed outside the cylinders.Computer simulations were performed that supported our interpretation of the behaviour observed in the experiments. In a series of experiments, a granular material in a rectangular container with two hollow cylinders was studied as it under underwent horizontal vibrations. At peak values ​​of acceleration, novel swirling granular flows were observed in the cylinder while the grains cascaded down the outer surface of the piles that formed outside the cylinders. Computer simulations were performed that supported our interpretation of the behavior observed in the experiments.