The Altar of Xiannong (God of Farming and Herbs), is a national-level Cultural Relics Preservation Unit at No. 21 Nongjing Road. Built in the 18th year of the Yongle period of the Ming Dynasty (A.D 1420), it was the altar where the emperors of the Ming and Qing dynasties (1368-1911) held ceremonies to offer sacrifices to the God Xiannong and to other gods, as well the place of planting for the royal family.

The main existing buildings are the Altar of the God Xiannong, the Temple of the God of Jupiter, the Hall of Worshiping, the Divine Kitchen, the Divine Storage, the Dressing Hall, the Platform of Viewing Planting and Qingcheng Hall. The building complex was slightly renovated but mainly remained the architectural style of the Ming Dynasty (1368-1644).

At the start of the agricultural season every spring, emperors of the Ming and Qing dynasties performed rituals to ensure that nature provided a bountiful harvest. In Jufu Hall, emperors literally put on new clothes; there they changed into farming costume to conduct ritual plowing to show respect to the god of agriculture.

The two Well Pavilions of the Divine Kitchen in Xiannong Altar, a complex of sacred buildings and storehouses, supplied water for emperors to draw when making sacrifices to the sacred forces of agriculture. These pavilions, both built in 1420, are distinguished by hexagonal roofs and a variety of dougongs (intricately carved brackets supporting interior beams). Center roof openings allowed the energy of the gods to penetrate the well water.

The restoration work of the altar began in 1988. By 2003, the major remedy works had completed, covering a total area of 2,361 square meters with special funds of 1.61 million yuan appropriated by the central government.