Iraqi cities on the Tigris River include Samarra and Mosul. Samarra is a city in Iraq located about 125 km north of Baghdad on the east bank of the Tigris River. It is known for its Great Mosque of al-Mutawakkil, which was built in 851 and is one of the oldest mosques in the world. Mosul is a city in northern Iraq located on the west bank of the Tigris River. It is the second largest city in Iraq and is known for its ancient ruins, including the 12th century Great Mosque of al-Nuri.