The Tigris River flows through Baghdad before joining the Euphrates system toward the Persian Gulf.
The Tigris rises in the Taurus Mountains of eastern Turkey and travels southeast through Turkey and Iraq. Baghdad, Iraq’s capital, stands on its banks, making the river central to the city’s history, water supply and identity.
Near the city of Al-Qurnah in southern Iraq, the Tigris joins the Euphrates to form the Shatt al-Arab waterway. That waterway then reaches the Persian Gulf. The combined river system supported some of the earliest complex civilizations in Mesopotamia, the region between the Tigris and Euphrates.
The Tigris is sometimes confused with the Euphrates because the two rivers run broadly parallel through Iraq and share the same ancient cultural region. They are separate rivers for most of their courses, but they merge before reaching the gulf.