The ruins of Dongyang City — the eastern capital of the Balhae kingdom — lie in the area around Hunchun and represent the most significant archaeological legacy of a state that once controlled this entire corner of northeast Asia. Balhae (698–926 CE) was a mixed Korean-Mohe polity that emerged after the destruction of the Goguryeo kingdom by Tang China and Silla Korea, establishing an empire that was sophisticated enough to model itself on Tang administrative systems while maintaining its distinct cultural identity.
Very little survives above ground — the Khitan conquest was thorough, and subsequent centuries of agricultural use have reduced the city to foundation traces and earthwork remnants. Archaeological excavations have recovered enough material to reconstruct the city's scale and layout, and a small museum at the site presents the findings. For anyone interested in the non-Chinese history of this region — the fact that Korean, Tungusic, and Mohe peoples built kingdoms here long before the Chinese state extended its control to the area — the site carries significance that the modest surface remains do not convey.