The Hindu Kush is an 800-kilometre-long (500 mi) mountain range that stretches near the Afghan-Pakistan border, from central Afghanistan to 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.
The origins of the name Hindu Kush are uncertain, with various theories being propounded by different scholars and writers. According to Hobson-Jobson, the name might be a possible corruption of Indicus Caucasus.