Abstract: An improved multi-unit railway car adapted to carry several intermodal cargo containers stacked in two tiers, with each of the several car units having substantially smooth side surfaces and including aerodynamic drag-reducing devices located at respective positions between adjacent car units and at each end of the multi-unit car. Between units are pairs of slender posts and, optionally, a slender crossbar, located so as to interrupt the gap between containers carried on adjacent units. At each end of the car, where there is a lengthier space, because of a four-wheeled truck and a coupler, is a pair of vertical panels with a small frontal area and an optional horizontal top member. For use on a car unit intended to carry short containers, the aerodynamic devices may be without the crossbar and horizontal top panel to provide clearance for a loader to handle lower tier containers.