Between Erzincan and Kemah it is joined by the Gönye River and passes through a rocky gorge.
[1] Near the small town of Kemaliye it receives its last tributary, the Çaltı Çayı, before turning sharply southeast to flow through a deep canyon[1] into the Keban Dam Lake on the Euphrates.
Before construction of the Keban Dam the Karasu joined the Murat River 10 km above the dam site and 13 km above the town of Keban.
[4] In 1996, 15 Turkish soldiers were killed when their personnel carrier fell into the river during a routine crossing.
[5] When temperatures in Turkey dropped below -25 °C in 2005 the river froze over and was used as a football pitch by locals.