An improved pile hammer provides a cylinder, such as one with a uniform interior diameter wall and uses a piston ram to cycle up and down therein to contact an anvil on a downstroke. The anvil preferably provides a cavity to both lessen the weight and improve upward force on the ram for the upstroke. An air inlet is preferably located above an air outlet which was not possible with prior art designs. An air reservoir can be located above and external to the wall in the cylinder.