Tigris << TY grihs >> River is a major river of southwestern Asia. It is about 1,180 miles (1,899 kilometers) long and forms part of the historic Tigris-Euphrates river system. The Tigris rises in mountainous terrain in eastern Turkey, flows southeast to the border between Turkey and Syria, and then enters Iraq. The river winds through Iraq and gradually descends to low flatland. At the town of Al Qurnah, Iraq, it joins the Euphrates River to form the Shatt al Arab. The Shatt al Arab flows into the Persian Gulf.
The area near and between the Tigris and Euphrates rivers has Iraq’s most fertile soil, and the rivers provide water for irrigation. Most of Iraq’s people live in this area. Baghdad, Iraq’s largest city, lies on the Tigris. Dams along the river in Iraq store water used to generate hydroelectric power. Small boats sail on the Tigris, but much of the river is too shallow for large vessels.
The Tigris-Euphrates region was the site of the world’s first civilization, which developed in Sumer about 3500 B.C. Assyria and other early civilizations also flourished in the region. The ruins of the Assyrian capital of Nineveh lie along the Tigris River.