The Esplanade of Sacrifice to the Heaven and Earth (; 南郊壇) is an imperial altar situated south of the city of Huế, central Vietnam. It also known as the Nam Giao altar. It is dedicated to the heaven and earth. The complex was visited by the monarchs of the Nguyễn dynasty for annual ceremonies of prayer to Heaven. History The ritual offerings to the Earth and Heaven predates the Nguyen dynasty. The earlier Hồ dynasty in the early 15th century CE also offered prayers. The emperor would proceed once a year in the grandest procession on elephants from the Imperial City to the temple. The procession would be accompanied by the playing of the Đăng đàn cung (, lit. Melody on the Ascent to the Esplanade) anthem. After the end of the monarchy in 1945, the altar fell into disuse and its state deteriorated. In recent decades steps have been taken to preserve and restore it. The altar was inscribed as part of the UNESCO World Heritage Site of "Complex of Hué Monuments" by the government in 1993 and is thus under special protection. The ritual worship of offering was revived in 2016, with local officials in attendance. The rite of Nam Giao The late night ceremonies of Nam Giao held in the Esplanade in the modern era were first held after many years as part of the Huế Festival in 2004, and are today held biennially with the officials of the Communist Party of Vietnam City Committee and the City People's Government of Huế, as well as the People's Committee and CPV Committee of the Thừa Thiên-Huế Province, in the name of the Central Committee of the CPV and the national government, presiding over the rites with village and neighborhood leaders in attendance together with business leaders and representatives of people's organizations. The ceremony, which is of Chinese origin and is similar to the Korean ceremony of Jongmyo jerye, was performed formerly by the Emperors of Vietnam for many years until 1945 after a three-day fast at the Trai Cung Palace, and today is a one-day event held as part of the Hue Festival, which by itself is a series of events celebrating the Imperial heritage of the city as the old residence of the Imperial Family of Vietnam. Unlike past ceremonies which were limited to the Imperial Family, government and military leaders and civil servants, the current ceremony