Tianning Temple
Thus, the City of Ji, ceded to the Liao as Youzhou, continued as Nanjing in what is today the southwest part of urban Beijing. Some of the oldest landmarks in southern Xicheng (formerly Xuanwu) and Fengtai Districts date to the Liao era. They include Sanmiao Road, one of the oldest streets in Beijing and the Niujie Mosque, founded in 996, and the Tianning Temple, built from 1100 to 1119. Under Liao rule, the population inside the walled city grew from 22,000 in 938 to 150,000 in 1113 (and the population of the surrounding region grew from 100,000 to 583,000) as large numbers of Khitan, Xi, Shiwei and Balhae from the north and Han from the south migrated to the city.