The Former Residence of Gan Xi was first built in the early years of the reign of the Qing Emperor Jiaqing (1796-1820). It is comprised of four groups of multi-row, hallway-style buildings, which are the typical Qing residential architectures in Nanjing. The residence combines the beauty and elegance of architectures in southern China and the simplicity and vigorousness of architectures in northern China. Its high walls, stepped gables, light hues, and unique folk decorations have conveyed the long history and profound cultural connotations of traditional residential buildings in Nanjing. From the vestibule to the backyard, the decoration styles and beam structures of the residence’s various halls and buildings are different. In between the high fire protection walls of the residence, compounds have formed. This unique multi-row, hallway-style buildings and the riverside buildings represent the two typical architectural forms of buildings in Nanjing. The Former Residence of Gan Xi was owned by the Jinling Gan family, an influential family in the Jiangnan region. The Gan family’s ancestry can be traced back to Gan Mao, prime minister of Qin in the Warring States period. Gan Ning, Gan Zhuo and other descendants of the family were all famous generals with great military exploits. Since the Qing dynasty, the Gan family has become famous for book collection, literature, and geoscience. The exhibition displays the family’s origin, genealogy, spirit, and representative figures. “Yougong (Fraternity) Hall” is a hall title of the Gan family at Nanbu Ting. It is also the title of the whole residence and the family. For more than 200 years, the “fraternity” spirit has been treated by ancestors of the Gan family as the norm for household management and interpersonal relations. “Yougong”, the two characters derived from the “Three-character Classic”, means that in a family, the older brothers should love his younger brothers, while the younger brothers should respect his older brothers. This norm for brother relations is expected to be further expanded to regulate relations between father and son, the elder and the young. In a family, if the father is caring, the children are dutiful, and brothers are friendly to each other, then the family must be a harmonious one, and a harmonious family always prospers.