Jiayu Pass, also called "China's No. 1 Pass", is located in the middle of the narrowest valley which is five kilometers to the west of Jiayuguan city in Gansu province. It is the gateway to the westernmost end of the Ming Dynasty Great Wall, and was historically known as the throat of Hexi area. Thanks to its strategically-important location and grand buildings, Jiayu Pass is nicknamed "Key of the Border".