The Pamir-Alay is a mountain system in Tajikistan, Kyrgyzstan and Uzbekistan, located north of the main range of the Pamir Mountains. It encompasses four main mountain ranges extending west from the Tian Shan Mountains. They are variously considered part of the Tian Shan, of the Pamir, or a separate mountain system. The term "Pamiro-Alay" is also used to refer to the mountain region encompassing the Pamir, the Pamir-Alay proper and the Tajik Depression.