Huangdi Mausoleum is the mausoleum of Xuanyuan, the ancestor of the Chinese nation. According to legend, Huangdi ascended to heaven, so the mausoleum is a clothing tomb. Located in Beiqiaoshan, Huangling County, Shaanxi Province, in 1961, the State Council announced that it was the first batch of national key cultural relics protection units, numbered "No. 1 Ancient Tomb", known as "No. 1 Tomb under the World". The Mausoleum of the Yellow Emperor, known as the "Bridge Mausoleum" in ancient times, is a place for Chinese emperors and famous people to worship the Yellow Emperor. According to records, the earliest sacrifice to the Yellow Emperor began in 442 B.C. Since the five years of the Tang Dynasty (770) when the temple was built, it has been the place where the state sacrifices were held in the dynasties.