"The types of relics from the four different periods vary from each other," Wang says. "It demonstrates the vital role of this region in the process forming an inclusive and diverse civilization. It provides important references on how a shared community was developed in North China."

Li Xinwei, a researcher with the Institute of Archaeology, Chinese Academy of Social Sciences, also sees Dengcaogouliang as the indicator of a bigger picture.

"The cylinder-shaped jars may represent a big cultural system," Li says. "And, in a later period of time, this place also had a unique and noticeable social development, despite the influence of other powerful cultures. There is so much to expect from upcoming excavations."

Song Xinchao, deputy director of the National Cultural Heritage Administration, says: "We did not expect to find such ancient heritage sites along the Great Wall, but discoveries at Dengcaogouliang and several other sites in recent years have reshaped our understanding.

"In the early stage of Chinese civilization, different cultures connected with, and influenced, each other," Song says. This helped nurture China as a country, he adds.