Old site introduction: The Red Building was built in 1918. It is an I-shaped building with a total of 4 floors and a brick and wood structure. The building is I-shaped in plan, 100 meters wide from east to west, 14 meters deep from north to south of the main building, and 34.34 meters deep from north to south of the east and west wings. It has a semi-basement and a total area of about 10,000 square meters. After the completion of the Red Building, it became the campus of the former Peking University, and served as a library and liberal arts classrooms. There is a printing shop in the semi-basement, the library on the first floor, administrative offices on the second floor, and classrooms on the third and fourth floors.