Rivers Arciniega and Llanteno. Both have their source in Sierra Salvada. The Arciniega receives in its upper basin the streams Angostina, Cozuela, Santa María del Castillo, Molino, Anguera, Fuente Zirian and Sojo. The Llanteno collects the streams that come down from Martijana, Añes and Lejarza, villages that are at the foot of the Angulo crag. It flows through Erbi, Retes de Llanteno, Llanteno, Inorza, Abiega and joins the Arciniega at Ureta. This river also bears the name of Ibalzibar. The Arciniega and the Llanteno join together and enter Biscay under the name of the Gordejuela river. It flows into the Cadagua, near Sodupe.