The northwestern, western, and southwestern parts of the province are all part of the vast North China Plain. The center of the province is more mountainous, with Mount Tai being the most prominent. The east of the province is the hilly Shandong Peninsula extending into the sea; it separates Bohai Sea in the northwest from the Yellow Sea to the east and south. The highest peak of Shandong is the highest peak in the Taishan area: Jade Emperor Peak, with a height of .