Its silhouette is familiar to all lovers of the Nile since the Middle Ages. It is a very old barge, perhaps the common ancestor of the first Arab dhows. It is a ship with a low draft, very low and very wide, with an enormous rudder, and with a very high prow. They are probably derived from the old square sailing barges used to transport stone blocks from quarries to the Pharaonic shipyards. the antenna of their mainsail is very long, and often the masts are hollowed out of notches intended to facilitate their climbing to brew the sails. The Gayassa uses its immense canopy to ascend the Nile to the south, and returns by the current.