Ancient Tombs at Longtou Mountain
The Ancient Tombs at Longtou Mountain are the burial sites of twelve royal figures from the Balhae (Bohai) kingdom. It is located on Longtou Mountain, southeast of Toudao Town (头道镇) in Helong, Jilin Province, China, a region possibly called the "Western Field of the Ran Valley" (染谷之西原) by the Balhae people.
Source: Wikipedia — Ancient Tombs at Longtou Mountain (CC BY-SA 4.0)