The Hindu Kush is a range of mountains. It starts near Pamir in the north of Gilgit extending in the southwest deep into the Khyber Pakhtunkhwa province of Pakistan, Tirich Mir is here. On the west of this range is some land called Wakhan corridor of Afghanistan which separates Gilgit Agency from the Tajikistan. This tract of land was formed under an agreement between the governments of the Empires of Russia and Britain in 1890, and the tract was annexed with Afghanistan to serve as a neutral zone between the two empires. The passes of Mintaka Pass, Kilik Pass, Chilinji Pass and Kuramber Pass are in Hindu Kush range and connect Kashmir with central Asian states. Many rivers including Chapursan River, Ishkuman River, Ghizar River, Gilgit River and Shandur River originate in the valleys of Hindukush and ultimately join the Indus River.