Atrek

The Atrek (Persian:اترک‎‎, Turkmen:Etrek derýasy), also known as the Attruck, Atrak, and Etrek, is a fast-moving river which begins in the mountains of north-eastern Iran (37°10′N 59°00′E / 37.167°N 59.000°E / 37.167; 59.000), and flows 563 kilometres (350 mi) westward draining into the south-eastern corner of the Caspian Sea in Turkmenistan. Because of the high use of its waters for irrigation, it only flows into the Caspian when it is in flood stage.