An aerodynamic cargo container with rounded rear doors is disclosed. The aerodynamic cargo container includes an angled rear area that reduces base drag when the container is transported. The rear sliding door allows for partial opening of the door and allows for operation of the door when the rear of the container is in close proximity to another object. The crash attenuating skirt deflects vehicles away from the cargo container. A pair of cargo doors may define the curved contour of the trailer rear section. These doors may have a plurality of pivoted and segmented sections that assume the curved contour of a stationary edge when the doors are moved to a closed position.