Baoji has written records that the "Yan Emperor Yuan" was built in 422 BC, that is, three years of Qin Linggong. This year, Qin Linggong "Wushan Yang" in the county town of Chencang District, "set the gong, sacrifice the Yan Emperor". "Yuan", "said Wenjie" release: "the heaven and the earth, the five emperors' base site sacrifice land." Although this is not what we call today, but this can be said to be the beginning of the ancient setting of "Yuan" sacrifice to Yan Emperor.