Euphrates Turkey, in Syria and in Iraq. The same figures are given by Isaev and Mikhailova. The length of the Shatt al-Arab, which connects the Euphrates and the Tigris with the Persian Gulf, is given by various sources as . Both the Kara Su and the Murat Su rise northwest from Lake Van at elevations of and amsl, respectively. At the location of the Keban Dam, the two rivers, now combined into the Euphrates, have dropped to an elevation of amsl. From Keban to the Syrian–Turkish border, the river drops another over a distance of less than . Once the Euphrates
Euphrates unrecorded substrate language. Tamaz V. Gamkrelidze and Vyacheslav Ivanov suggest the Proto-Sumerian *burudu "copper" (Sumerian "urudu") as an origin, with an explanation that Euphrates was the river by which the copper ore was transported in rafts, since Mesopotamia was the center of copper metallurgy during the period. The earliest references to the Euphrates come from cuneiform texts found in Shuruppak and pre-Sargonic Nippur in southern Iraq and date to the mid-3rd millennium BCE. In these texts, written in Sumerian, the Euphrates is called "Buranuna" (logographic: UD.KIB.NUN). The name could also be written KIB.NUN.(NA) or KIB.NUN, with the prefix "" indicating