It is formed at the confluence of the rivers Rudkhaneye-Fekhlian (Fahlian), and Rude-Tenge-Shu (Tang Shiv), which flow from the southern slopes of the Zagros mountains northwest of the city of Nurabad, Fars to the south-west of Yasuj, in the Fars province.

[4] At the mouth of the river, the fleet of Nearchus (360–300 BC), an associate of Alexander the Great, stopped to rest and to take on water for five days to sail along the shores of Susiana.

The town of Alexandria Carmania was founded by Alexander in January 324 BC after his army had reunited with Nearchus and his men who had beached their boats near the mouth of the Minab River, further down along the south coast of Iran in Hormozgan province.

The research continues in the area south of the modern city of Behbahan in Khuzestan province.

[6] To the north, the Behbahan plain, intersected by Marun River, is also a closely associated area.