Tongwancheng

Tongwancheng was the capital of the Xiongnu-led Hu Xia dynasty in northern China during the Sixteen Kingdoms period in the early 5th century. The city is at the southern edge of the Maowusu Sands of the Ordos Desert, on what was formerly a strategic site in the center of the Ordos Plateau. Tongwancheng, which means the "city ruling ten thousand", is the largest urban center of the Southern Xiongnu that has ever been found. The city's ruins are well preserved and located in Jingbian County, Shaanxi Province, near the border with Inner Mongolia. The city has been surveyed and has had some elements restored, but not yet fully excavated.

The city was built by around 100,000 Xiongnu of the Hu Xia dynasty under the command of Helian Bobo in 419. Helian Bobo, also known by his sinified surname as Liu Bobo, was a descendant of the Xiongnu chanyu who founded their steppe empire in the 3rd century BC. Helian Bobo died in 425 AD, and Helian Chang succeeded him as ruler of the city.

Source: Wikipedia