In the early 20th century there were no known fully wood-constructed Tang Dynasty buildings that still existed; the oldest so far discovered was the 1931 find of Guanyin Pavilion at Dule Monastery, dated 984 during the Song. This was until the architectural historians Liang Sicheng (1901-1972), Lin Huiyin (1904-1955), Mo Zongjiang (1916-1999), and (1902 - c. 1960s) discovered that the Great East Hall of Foguang Temple on Mount Wutai in Shanxi was reliably dated to the year 857 in June 1937. The groundfloor dimensions for this monastic hall measures . A year after the discovery at Foguang, the main hall of nearby Nanchan Temple on Mount Wutai was reliably dated to the year 782, while a total of six Tang era wooden buildings have been found by the 21st century. The oldest existent fully wooden pagoda that has survived intact is the Pagoda of Fogong Temple of the Liao dynasty, located in Ying County of Shanxi. While the East Hall of Foguang Temple features only seven types of bracket arms in its construction, the 11th-century Pagoda of Fogong Temple features a total of fifty-four.