Introduction to the Yi Cheng Office: The Yi Cheng Office is located on the north side of Toudao Street. It was the core of the post city in the Qing Dynasty. It was the office of the highest administrative official Yi Cheng and his staff. It is an important administrative agency and is responsible for all the posts. matters. There are two courtyards, the front hall and the back house, and a back garden. The back garden is located in the backyard of the back house. It is a place where Yi Cheng and his family live and relax. There are hanging flower gate tower, Taihu stone, water well and back pavilion in the garden.