" Complete Library of the Four Treasuries," also known as "The Imperially Commissioned Complete Library of the Four Treasuries," is a large-scale compilation of books edited by scholars such as Yong Rong and Ji Yun. It consists of four sections: Confucian Classics, History, Philosophy, and Literature, hence the name "Four Treasuries." The compilation was completed in the 57th year of the Qianlong reign (1792). During the compilation process, book dealers from various regions set up stalls and shops here, selling a large number of books. The gathering of scholars and booksellers during the compilation of the Four Treasuries gave rise to the unique Changdian culture in old Beijing, with the most famous cultural street being Liulichang, located in the east of Xuanwumen.