The Karkas mountain chain ( Reshteh kuh-e Karkas ) is located in Central Iran.
It ranges from Kashan to Ardestan over more than 100 km and is mainly composed of igneous (plutonic and volcanic), pyroclastic and somewhat sedimentary Tertiary rocks. In the central part, this mountain chain consists of a Precambrian-Paleozoic basement.
The highest peak of the Karkas Mountains is 3895m which is close to Natanz.
Although in Persian karkas means vulture, it is possible that the name of this mountain chain is derived from the settlement activity of ancient Kassites in the area, since in the ancient Assyrian language Kar-Kassi means "town or land of the Kassites" (modified interpretation after Roman Ghirshman, 1954).