The Roman cargo par excellence, was a ship of great size, drawing water and tonnage.

If the documentation does not abound more for the Roman Cargoes than for the other units, this type of ship is better known than the trireme because of the enormity of its cargo, responsible for its shipwreck, unlike the galleys of war, Unsinkable. Greek and Roman cargo ships indeed constellate the bottom of the Mediterranean, under heaps of amphorae very well preserved. Although the extreme antiquity of these wrecks does not facilitate the task of the archaeologist divers due to the dilapidated state of the wooden structure, one can always complete the basic patterns by cross-checking them with bas-reliefs and frescoes found during centuries. The "Corbite" seemed to be a derivative of the Phoenician freighter, the Gaoul, characterized by a swan in figure of stern and a gallery. The first had a sailboat stitched, with an interrupted rail to facilitate loading.

The last, Romans, presented the culmination, with a very large shell. To facilitate his maneuver he has a sail called "artémon", ancestor of trinquet de beaupré. The mainsail is generally surmounted by a very recognizable triangular sail of arrow, the Supparum, generally red. The biggest of them were Onerariae, they were real "monsters" for the time, more than 55 meters long by 13 of the keel to the Tillac and 14 wide, able to carry until 2000 Tons (the equivalent of 40,000 amphoras!) In general of wheat from Sicily. These onerariae were generally grouped in convoy and protected by the fleet in order to guard against any pirate attack. These Roman cargo ships were also supposed to carry up to 400 passengers under Spartan conditions. Having no place for possible rowers, the navigation of these freighters returning from Alexandria or Sicily was very slow and they practiced cabotage as far as Ostia.