An auto rack rail road car has a main deck and upper deck. It is provided with a door for controlling access thereto. The door is a radial arm door, and has a ladder mounted thereon by which personnel can ascend the second deck when the door is open. A second ladder is mounted to the first deck so that when the door is open the second ladder is positioned to co-operate with the first ladder. The arcuate path of the door is free from overhanging obstructions. The door also has internal and external weld-free stiffeners member for enhancing the rigidity thereof. A roller mounted to the door permits the door to be moved between open and closed positions. The door may further include a lock. A guide member protruding from the door co-operates with a groove in the main deck which slidingly guides the door as it moves between open and closed positions to control access to the car.