A Ro-Ro (Roll-on Roll-off) vessel is designed to transport motor vehicles or any other rolling stock. Distinguishing Features: Ro-Ro vessels have a hinged ramp, typically offset at the stern, that allows motor vehicles (automobiles, trucks, trailers, farm tractors, etc.) to drive on and off the vessel. Size or Length: Ro-Ro vessels are typically very large. The largest Ro-Ro vessel is 789.34ft (240.6m) in length, with a tonnage of 67,140 gross tons and 34,376 dwt.