Heilongjiang province: The Jin Boundary Trench

Heilongjiang, China's northernmost province, preserves Great Wall sections built during the Tang (618-907) and Jurchen Jin(1115-1234) dynasties, with a total length of 266.285 kilometers. They are the Mudan River Frontier Wall built by the Bohai Kingdom (698-926, (a minority regime in northeastern China established by the ancient Mohe people)) during the Tang Dynasty, and the Great Wall of Jurchen Jin Dynasty, which is also called the Jin Boundary Trench (most of which is in Inner Mongolia to the west of Heilongjiang province).

The length of the Great Wall of the Jin Boundary Trench in Heilongjiang is 200.266 kilometers, accounting for the vast majority of the province’s Great Wall resources. It is also a national foremost protected cultural heritage site .

The Great Wall dating to the Jurchen Jin Dynasty , with a total length of more than 4,500 kilometers, was built by the Jurchen Jin people to defend against Mongol forces from the north. It was mainly designed to defend against cavalry and was therefore fortified with earthen trenches.