The natural barrier or restriction which controlled the Chinese settlement or agreement to the west is known as the Gobi desert. Gobi Desert which is known as one of the largest deserts in the world is situated in China and Mongolia.
The Gobi desert stretches from the eastern hills of Pamir in the west to the Khingan ranges in the east and from the Altai, Khangai and Yablonoi ranges in the north to the Altine and Nanshan hills in the south. The western part of this desert is a part of the Tarim Basin.
