Answer: In 539 BCE Cyrus invaded the Babylonian Empire, following the banks of the Gyndes on his way to Babylon. He allegedly dug canals to divert the river's stream, making it easier to cross. Cyrus met and routed the Babylonian army in battle near Opis, where the Diyala flows into the Tigris. Cyrus the great won four battles in His lifetime. One of them being, the battle of the Granicus.
Explanation: Hope this helps. :))
