Shanxi is located on a plateau made up of higher ground to the east (Taihang Mountains) and the west (Lüliang Mountains) and a series of valleys in the center through which the Fen River runs. The highest peak is Mount Wutai (Wutai Shan) in northeastern Shanxi with an altitude of 3,058 m. The Great Wall of China forms most of the northern border with Inner Mongolia. The Zhongtiao Mountains run along part of the southern border and separate Shanxi from the east-west part of the Yellow River. Mount Hua is to the southwest.