Kaicheng Stone Classics
The Kaicheng Stone Classics (開成石經) or Tang Stone Classics are a group of twelve early Chinese classic works carved on the orders of Emperor Wenzong of the Tang dynasty in 833–837 (Kaicheng era) as a reference document for scholars. The works recorded are: The classics, with more than 650,000 characters engraved double-sided on 114 stone tablets, are preserved in the Stele Forest Museum in Xi'an, China. Widely regarded as the world's heaviest books, these tablets are also among the most complete copies of these key documents of Chinese culture to ever have existed. Other stone  Confucian classics. The Confucian classics have been engraved on stone tablets several times. The Xiping Stone Classics or Han Stone Classics were set up at the Imperial Academy outside Luoyang in 175–183. Around 200,000 characters were inscribed on 46 stelae, comprising the text of the seven classics recognized at the time: the "Book of Changes", "Book of Documents", "Book of Songs", "Book of Rites", "Spring and Autumn Annals", "Classic of Filial Piety" and "Analects". Only a few fragments of these tablets have survived. The Zhengshi () classics in 241 recorded three classics in three scripts, but these have since disappeared. Later  stone classics are Guangzheng () (944), Jiayou () (1061) and Taixue (1131). During the Song dynasty, the "Mencius" was also recognized as part of the Confucian canon, making thirteen classic works. It was also included in tablets engraved in 1789 during the reign of the Qianlong Emperor in the Qing dynasty, adding a further 30,000 characters on 17 tablets. The complete set of 190 tablets containing over 630,000 characters is kept in the Beijing Temple of Confucius.