阴山
Eventually the sand dunes cross over to the left bank of the Yellow River where they are threaded by the beds of dry watercourses. The Yin Mountains, which stretch from 108° to 112° E in the north of the great bend of the Yellow River, have a wild alpine character and are distinguished from other mountains in the southeast of Mongolia by an abundance of both water and vegetation. In one of their constituent ranges, the bold Muni-uul, long and nearly wide, they attain elevations of , and have steep flanks, slashed with rugged gorges and narrow glens.