Tongwan City is located at the junction of Ordos City and Jingbian, Shaanxi Province. It was the capital of the Daxia Kingdom during the Northern Dynasties and Sixteen Kingdoms 1500 years ago, In 407 AD, the Xiongnu leader Helian Bobo called himself “Tianwang, Great Chan Yu, occupied and located in the desert. The first year of Helian Bobo's kingdom called "Fengxiang", the 100,000 people of all ethnic groups, used the "steaming dust to build the city" method to build the capital in the south of the black water in the north of the SuFang (now Hongliu River). The city was built in 7 years. The city is 25 meters thick, with a height of 23.33 meters and a width of 11.16 meters.