Located beside Jingbian County of Yulin City is the world famous Tongwancheng, which is also called Helian City in honor of his founder Helian Bobo, one influential noble of Southern Xiongnu regime in the Eastern Jin Dynasty.

As relic of the capital city of Greco-Bactrian Kingdom, Tongwancheng is also the sole capital city left by Xiongnu people throughout history, and the earliest and the most famed capital city in Northern China with near 1,600 years of history. Tongwancheng was recognized as key cultural relic under the state protection in 1996.