The river known for its delta located in southern Iraq is the Euphrates. It is one of the two major rivers in the Mesopotamian region, along with the Tigris. The Euphrates River flows through various countries, including Turkey and Syria, before emptying into the Persian Gulf. Its delta is vital for agriculture in Iraq, providing fertile land for crops. The Euphrates has been central to the development of ancient civilizations and remains significant for water resources in the region today.