The Hindu Kush (; Pashto, Persian and ), also known in Ancient Greek as the Caucasus Indicus or Paropamisadae , is an mountain range that stretches between central Afghanistan and northern Pakistan. It forms the western section of the Hindu Kush Himalayan Region (HKH). It divides the valley of the Amu Darya (the ancient Oxus) to the north from the Indus River valley to the south.