WebGansu is an inland province in Northwestern China.Its capital and largest city is Lanzhou, in the southeast part of the province.. The seventh-largest administrative district by area at 453,700 square kilometres (175,200 sq mi), Gansu lies between the Tibetan and Loess plateaus and borders Mongolia's Govi-Altai Province, Inner Mongolia and Ningxia to the north, Xinjiang and Qinghai to the west ...