Jordan, river, c.200 mi (320 km) long, formed in the Hula basin, N Israel, by the confluence of three headwater streams and meandering S through the Sea of Galilee to the Dead Sea; the region of Palestine's longest and most important river and the world's lowest river below sea level. It flows through the northern section of the Jordan trough, a part of the Great Rift Valley; between the Sea of Galilee and the Dead Sea, the Jordan valley is called the Ghor. There it forms the border between Israel and the West Bank (W) and the nation of Jordan (E). The Jordan is fed by many small streams, with headwaters in Syria and Lebanon. The Yarmuk River is its largest tributary. Deep and turbulent during the rainy season, the Jordan is reduced to a sluggish, shallow stream during the summer. As it nears the Dead Sea, its salinity increases. Although the river is not navigable, its waters are valuable for irrigation. Israel's National Water Carrier Project uses the Sea of Galilee as a reservoir, and Jordan's East Ghor project diverts water from the Yarmuk River. Other irrigation projects, in Syria and Lebanon, divert water from the Jordan's headstreams. This extensive use of the river and its tributaries for irrigation has depleted the flow into the Dead Sea and greatly increased pollution in the Jordan. The river is mentioned in the New Testament as the scene of Jesus' baptism.