Abstract: A parking lot gate control system having a pivoted normally horizontal gate bar which is automatically elevated to a raised non-obstructing position and then returned to its normal position by a mechanism driven by an electric motor under the control of a circuit including a clearance device at the entrance to the parking lot consisting of a switch unit operated by an identification card or coin and a car presence-sensing loop in the roadway beyond the clearance device. The circuit operates to raise the gate bar after a proper card or coin has been inserted in the clearance device; thereafter, the vehicle moves onto the loop. The gate bar descends after the vehicle leaves the loop. If another card or coin is inserted in the clearance device by the operator of a second car while the gate bar is descending, the gate bar reverses its downward movement and stays up until the second car has left the loop.