Yongtai City Site, located in Yongtai Village, Sitan Town, Jingtai County, Baiyin City, Gansu Province, also known as Guicheng, is a large-scale earthen fortified city built during the Ming and Qing Dynasties, dating back to the 35th year of the Wanli reign (1607). The site is 520 meters long from east to west and 500 meters wide from north to south, covering an area of over 300,000 square meters. The city walls are constructed of rammed earth mixed with sand, reaching a height of 8-12 meters, with a base width of 6 meters and a top width of 5 meters. Semi-circular barbicans were built on the east, west, and north sides of the city. The city gates opened to the south and were surrounded by barbicans. Twelve watchtowers (or ramparts) were also present around the city. Archaeological exploration in 2017 revealed that only the flood control ditches on the east and west sides of the moat remain. Stone tablets and other artifacts were unearthed at the site. This ancient city was an important stronghold in the new border defense system of Gansu during the Ming Dynasty. Construction began in 1607 (the 36th year of the Wanli Emperor's reign) and was completed in 1608 (the 37th year of the Wanli Emperor's reign) under the supervision of Xing Yunlu, the Deputy Military Commissioner. In 1724 (the 2nd year of the Yongzheng Emperor's reign), Yue Zhongqi added the Five-Eyed Well and the Ganlu Pond water system. In 1914 (the 3rd year of the Republic of China), Yongtai Primary School, a school combining Chinese and Western styles with a Gothic influence, was established. It closed in 2014 and was converted into a museum. The ancient city contains ancient architectural complexes such as the Great Buddha Temple, the Zhushen Pavilion, and the Jade Emperor Hall, as well as several memorial archways, and is hailed as a textbook example of ancient Chinese military fortresses. In May 2006, it was listed as a sixth batch of National Key Cultural Relics Protection Units and was designated a Historical and Cultural Village of Gansu Province in the same year.