The Millet Valley Mountain is a famous mountain in the Yan area, located in the east of Jingliyuan Village, 8 kilometers south of Miyun County. Millet Valley Mountain is also known as "Millet Valley Spring Back" or "Millet Valley First Spring", one of the eight outer scenes of Miyun County. During the Spring and Autumn Period and Warring States Period, Millet Valley Mountain was in the Yan area, and there are inscriptions such as "Millet Valley Yan Mountain..." on the stele of the Millet Valley Mountain Temple rebuilt by Prince Dan of the Yan State.