贺兰山
Inner Mongolia largely consists of the northern side of the North China Craton, a tilted and sedimented Precambrian block. In the extreme southwest is the edge of the Tibetan Plateau where the autonomous region's highest peak, Main Peak in the Helan Mountains reaches , and is still being pushed up today in short bursts. Most of Inner Mongolia is a plateau averaging around in altitude and covered by extensive loess and sand deposits. The northern part consists of the Mesozoic era Khingan Mountains, and is owing to the cooler climate more forested, chiefly with Manchurian elm, ash, birch, Mongolian oak and a number of pine and spruce species. Where discontinuous permafrost is present north of Hailar District, forests are almost exclusively coniferous. In the south, the natural vegetation is grassland in the east and very sparse in the arid west, and grazing is the dominant economic activity.