Archaeologists have discovered remnants of a Sui Dynasty (581-618) section of the Great Wall in Beijing for the first time, providing fresh insights into the ancient fortification's development in northern China and the region's early military defense system.

The discovery was announced at the Fourth Beijing-Tianjin-Hebei Archaeological Academic Exchange, held in Beijing on Saturday. The discovery was made during an excavation at the Dalinggou site, an early-stage Great Wall military outpost in Changping district.

The excavations, conducted by the Beijing Institute of Archaeology from August to October, covered an area of 800 square meters. Archaeologists unearthed more than 60 ceramic and metal artifacts, including architectural components, items of daily use and weapons, dating to three historical periods: the Northern Qi Dynasty (550-577), the Sui Dynasty and the Jin Dynasty (1115-1234).

According to Shang Heng from the Beijing Institute of Archaeology, the project's lead archaeologist, the site was previously identified as part of the Northern Qi Great Wall following a nationwide survey. However, archaeological evidence has now established that it was also in use during the Sui Dynasty.

The conclusion is supported by discoveries of a Sui Dynasty wuzhu coin and a piece of porcelain displaying characteristics typical of the period. Wuzhu was a standard bronze cash coin in ancient China, famous for being the longest-circulating currency in Chinese history.

Geographical evidence further supports the finding. The Dalinggou site lies along the same defensive line as several previously identified Sui Dynasty Great Wall remains in neighboring provinces.

To the west, a stone inscription recording the construction of the Great Wall in 599 was found in Kelan county, Shanxi province. To the east, another inscription dating to 597 was found in Luanping county, Hebei province. A Sui Dynasty beacon tower has also been identified in Qianxi county, Hebei.

The Sui Dynasty was a short-lived but pivotal dynasty in Chinese history. It ended political division by reunifying China in 589 and laid the foundation for the Tang Dynasty (618-907).

The Sui Dynasty was known for its administrative reforms, expansion of central government authority and major infrastructure projects. One of the most significant achievements of the Sui Dynasty was the construction and expansion of the Grand Canal, an extensive network of waterways that connected northern and southern China and facilitated the transportation of grain, goods and troops.

Valuable basis

Shang noted that the new finding offers a valuable basis for archaeological research into the dynasty's defense system across North China.

"The latest discovery will help refine understanding of the early Great Wall's chronology, location, route and military defense system in Beijing, while providing new evidence for tracing the course of Sui Dynasty fortifications in Shanxi and Hebei," he said.

The excavation also sheds light on the construction techniques and scale of early Great Wall fortifications.

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Although remains of the residential quarters that once existed near the outpost have been severely damaged by years of shallow burials and modern agricultural activities, leaving very few well-preserved traces of daily life or samples suitable for archaeological analysis, researchers have identified important structural features.

"The entrance, for example, was built using a jamb column timber framework, with vertically arranged columns installed along both sides of the gate passage, an architectural form widely used from the Han Dynasty (206 BC to AD 220) through the Sui and Tang dynasties," Shang said.

The scale of construction challenges previous assumptions that early Great Wall sections were relatively narrow and resembled small stone boundaries. Instead, the findings suggest that considerable labor and material resources were invested in constructing the frontier defenses.

Li Ren contributed to this story.

Contact the writers at wangkaihao@chinadaily.com.cn