Like most Viking boats tied in sagas, the Byrding is quite old difficult to date until a wreck is found. The Byrding was a smaller version of the Knarr, smaller even than the Karv, a merchant coastal vessel. It was narrower than the latter, and also shorter (an indication of size is given through record of it having between "10 and 15 roms" - spaces between the benches). Probably, its size should have been around 12-17 meters. It was midway between the Karv, half-civilian half-military design, and the Knorr, a pure cargo boat. With large sails, these were thus considered very good walkers, fast, with straight bow and stern cutters. This boat was also capable of deep-sea navigation over respectable distances, such as between Iceland and Norway. During the great military expeditions, they were probably used to carry everything that the great langskips could not carry like food and water. With Christianization and adoption of southern roundships, the Byrding began to disappear.