The Dyfne or Dyphne is a river about three days' walk from the border which divides Aedirn and Kaedwen. The river originates in the Blue Mountains and flows westward through Dol Blathanna until it ultimately joins the Pontar. Gulet is located south of the Dyfne.
It was on a bridge over the Dyfne that Margreve Mansfeld of Ard Carraigh and marshal Menno Coehoorn embraced and shook hands, according to Dandelion.