Karkheh River

The river rises in the Zagros Mountains, and passes west of Shush (ancient Susa), eventually falling in ancient times into the Tigris just below its confluence with the Euphrates very near to the Iran-Iraq border.

In modern times, after approaching within 16 kilometres (10 mi) of the Dez River, it turns to the southwest and then, northwest of Ahvaz, turns northwest and is absorbed by the Hawizeh Marshes that straddle the Iran–Iraq border.

[3] Ancient names for the Karkheh should be treated as conjectural because the bed of the river has changed in historic times, and because a nearby watercourse between the Karkheh and the Dez River, the Shaur, confuses the identification.

[4] The problem with the ancient names is that while the Karkheh flows a kilometre or two west of Susa, another major watercourse flows parallel to the Karkheh within a few kilometres east of Susa.

The watercourse a kilometre or two east of Susa, now called the Shaur, flows east between the Haft Tepe and Shaur ridges into the Dez River, north of where the Dez and Karun rivers merge.