Gansu lies between the Tibetan Plateau and the Loess Plateau, bordering Mongolia (Govi-Altai Province) to the northwest, Inner Mongolia and Ningxia to the north, Shaanxi to the east, Sichuan to the south, and Xinjiang to the west. The Yellow River passes through the southern part of the province. The province contains the geographical centre of China, marked by the Center of the Country Monument at . Part of the Gobi Desert is located in Gansu, as well as small parts of the Badain Jaran Desert and the Tengger Desert. The Yellow River gets most of its water from Gansu, flowing straight
Environmental issues in China the country. Approximately 30% of China's surface area is desert. China's rapid industrialization could cause this area to drastically increase. The Gobi Desert in the north currently expands by about per year. The vast plains in northern China used to be regularly flooded by the Yellow River. However, overgrazing and the expansion of agricultural land could cause this area to increase. In 2009, it was estimated that over 200 high-altitude lakes in Zoigê Marsh, which provides 30% of the Yellow River's water, had dried up. In 2001, China initiated a "Green Wall of China" project. It is a project to