The Euphrates (Arabic: Firat) is the western member of the pair of great rivers that define Mesopotamia, along with the Tigris, which flows from the mountains of Anatolia through Iraq. The river then merges with the Tigris in southern Iraq to form the Shatt al-Arab, which in turn flows on into the Persian Gulf. In the Bible it is referred to as "The River".
Euphrates in Mythology The river Euphrates is an ancient river referred to in the Bible as far back as the Garden of Eden in Genesis 2. It is the fourth river, after Pishon[?], Gihon[?], and Tigris, to form from the river flowing out of the garden. The river also marked one of the boundaries of the land promised by God to Abraham and his descendants.
Because of their origin in the Judeo-Christian view of the beginning of time, the Euphrates and the Tigris are thought to be the rivers where life itself began.
See also Tigris-Euphrates alluvial salt marsh