Nahal Kziv or the Horn Valley is a 39-kilometer long perennial stream in the Upper Galilee, Israel. During the winter, rainfall fills the channel, and springs along the riverbed add to the flow. Currently, Mekorot pumps the water of the river's principal spring, Ein Ziv, and supplies it to the residents of the Western Galilee, making the channel between Ein Ziv and Ein Tamir an intermittent stream. On the southern ridge overlooking the valley sits a 12th-century Crusader castle, Montfort, the old headquarters of the Teutonic Order in the Holy Land.