The Beijing section of the Great Wall winds from east to west through the six districts of Pinggu, Miyun, Huairou, Yanqing, Changping and Mentougou. Beijing took the Jiankou Great Wall and the Dazhuang Ke Great Wall as pilots, and took the lead in introducing archaeological excavations in the repair of the Great Wall in the country, and began the transformation from general rescue reinforcement to research repair. This year, Beijing has made a series of achievements in the construction of the Great Wall National Cultural Park (Beijing Section), the protection of the Great Wall, and the archaeology of the Great Wall.

This issue of "A Question to the End" focuses on how the soldiers of the border soldiers lived on the Great Wall back then. In addition, there are questions such as how to accurately determine the construction age of the Great Wall and why archaeological excavations should be introduced in the repair process of the Great Wall.

How to restore the life of the soldiers on the border with the remains of the fire kang stove site?

In this scientific expedition, in the western section of the Badaling Great Wall, archaeologists found the remains of living facilities such as fire kang and stove sites in the Ming Dynasty on the top of the enemy platform, which refers to the tower on the wall of the Great Wall used to defend against the enemy. Let's see what kind of stories these ruins can restore.

In the archaeological process of the western section of the Badaling Great Wall, the remains of living facilities such as the fire kang and stove site of the Ming Dynasty were also found in the No. 64 enemy platform, and the living utensils such as pots, plates, bowls, scissors, shovels and so on were unearthed, which restored the daily life of the soldiers in the Ming Dynasty.

Yu Haikuan, deputy director of the Cultural Relics Institute of Yanqing District, Beijing: At that time, we found three ondols, one in this corner, then one in this corner, and one in the northeast corner. The ruins of the ondol were preserved.

On the day of the interview, the reporter found that the wind was very strong outside, but the position of the fire kang inside the enemy platform could hardly blow the wind. Archaeologists believe that these ondol remains are very helpful for studying the life of the ancient garrison.

Yu Haikuan, deputy director of the Cultural Relics Institute of Yanqing District, Beijing: The discovery of these ondols shows that the first is that our area must have been very cold in the Ming Dynasty, the second shows that there were also garrisons in winter at that time, and the third shows that the defensive pressure is very high, so there are also people on duty at night and night.

With the erosion of time, many parts of Enemy Platform 64 have been damaged. But some details still show that this enemy platform was like a protective house in the Ming Dynasty, with a roof and wooden windows.

Yu Haikuan, deputy director of the Cultural Relics Institute of Yanqing District, Beijing: This trace, this is the location of a wooden window at that time, which shows that at that time, in addition to the roof, all the holes and windows were closed, and it was an independent space that could provide heating services in winter.

What do the soldiers on the Great Wall eat? Is there entertainment?

The reporter learned from the Beijing Municipal Institute of Archaeology that the cultural relics unearthed from the archaeology of the Beijing Great Wall in recent years are mainly divided into three categories, one is the building components of the Great Wall, the other is weapons, and the third is daily necessities. In the film just now, various traces of life found in the archaeological process of the Great Wall were introduced. So what did the soldiers who lived here eat at that time? Do you have any entertainment? The discovery on the Great Wall of Dazhuang Branch provides the answer.

In 2022, researchers discovered carbonized grain from the Ming Dynasty on the Great Wall of Dazhuang in Yanqing District, Beijing.

Shang Heng, deputy research librarian of the Beijing Municipal Institute of Archaeology: It is said that there are millet, millet, rice, and pepper, although these food crops have been carbonized. But it truly restores the daily life and food of the Great Wall guards, which is a common concern of the public, what people ate at that time.

Chen Mingjie, Director of the Beijing Municipal Bureau of Cultural Relics: Everyone may also be concerned about whether there are entertainment activities, will they be boring? In our archaeological discoveries, we found something like backgammon, which shows that these soldiers who guard the frontier still have some very interesting cultural and recreational activities, and some archaeological discoveries are very down-to-earth. Such down-to-earth content is indeed basically not recorded in traditional historical documents, so it can provide fresh materials through archaeology, enrich the content of the Great Wall cultural display and dissemination, and also allow the public to have more experience on the Great Wall.

How to use carbon-14 dating to determine the age of the Great Wall?

The survey of the Great Wall in Beijing used the integration of archaeology, historical geography, digitization and other disciplines to obtain the survey results, and for the first time used carbon-14 technology to determine the age of the construction of the Great Wall. How?

Previously, archaeologists believed that it was more likely that the Great Wall in the Majiaoquan section of Changping District was the Great Wall of the Northern Qi Dynasty. According to the records of the Book of Northern Qi, the Northern Qi Kingdom once built the Great Wall on a large scale, from today's Datong in Shanxi Province to the shore of the Bohai Sea, and clearly recorded that the route passed through the "Youzhou Beixiakou", that is, today's Changping Nankou area, not far from the Great Wall of the Majiaquan section. It is speculated that this section of the ancient Great Wall was probably built during that period. But because there is no more evidence, the possibility that it is the Great Wall of Yan cannot be ruled out.

Li Weiwei, Research Librarian of Beijing Institute of Archaeology: From the pottery shards, charcoal blocks, and tiles collected by traditional archaeological methods on site, we will conduct carbon-14 or thermal spectroscopy analysis to obtain more scientific information data.

Carbon-14 technology dating, a measurement method that calculates the approximate age of a sample based on the degree of decay of carbon-14, has been widely used in archaeological work today. In the course of this investigation, the carbon-14 dating of the Great Wall of the Majiaoquan section confirmed that the Great Wall of the Majiaoquan section of Changping District was built from 536 to 646 A.D., ruling out the possibility that it was the Yan Great Wall.

Chen Mingjie, director of the Beijing Municipal Bureau of Cultural Relics: The use of carbon-14 technology dating has made it clear that the era of the Great Wall in the Majiaoquan section of Changping District is the Northern Qi Dynasty.

Preserve the original style How to "repair the old as the old"?

At present, the two pilot projects of the Great Wall of Yanqing Dazhuang Branch in Beijing and the Great Wall of Huairou Jiankou have entered the repair stage, and Beijing has always adhered to the principle of "repairing the old as the old" in the repair of the Great Wall, trying to use old bricks and following the ancient methods, and retaining the "old" of the Great Wall under the premise of ensuring the safety of the Great Wall.

Reporter Shao Wei: At present, we are located in the No. 145 enemy station in the corner building of the Jiankou Great Wall, which has been renovated by research, and still retains the old appearance of the Great Wall, and the invasive plants that damaged the wall in the distance have been cut down and only the roots remain, and under the condition of ensuring the safety of the Great Wall itself, several clusters of vegetation next to it have been retained, which is also convenient for us to understand the root cause of the Great Wall disease and the timing of the collapse. On the left-hand side, you can see the entrance to the ancient kang and stove site, which is a kang surface mixed with loess and hay after modern restoration. The cement brick joints will be yellow and gray compared with the original ancient buildings. During the research repair, the old bricks will be used as repair stones in accordance with the principle of "local materials" of the ancients, which is to carry out research on the value of cultural relics while protecting and repairing.

"Minimal intervention and repairing the old as the old" is the mature experience of Beijing's restoration of the Great Wall in recent years. Archaeologists said that the remnants were originally part of the culture of the ancient ruins of the Great Wall, and choosing to retain this collapse state rather than restore it can allow more people to understand the root cause of the wall disease and the timing of the collapse.

The reporter saw two relatively complete piles of broken bricks at the repair site of the Great Wall in Dazhuang, Yanqing, and the cultural preservation workers said that these bricks were the main raw materials for the repair.

Yu Haikuan, deputy director of the Cultural Relics Institute of Yanqing District, Beijing: We have screened out these broken ash and bricks through the soil layer after cleaning, and we will follow up according to the cultural relics repair, there is a called recognizability, in the missing part, use the existing broken bricks and ash to fill it with a recognizable protection, because there is no mortar in the broken bricks, so the water can be discharged smoothly, and at the same time, it also ensures that we have completed the repair. This Great Wall has a relatively complete and recognizable end effect.

Why was archaeological excavation first introduced in the restoration of the Great Wall?

Since 2021, in order to further strengthen the protection of the Great Wall, Beijing has taken the lead in introducing archaeological excavations in the restoration of the Great Wall. What are the benefits of this?

Reporter Shao Wei: After a one-hour hike, I have now arrived at the No. 1 enemy tower guarded by the general of the Jiankou Great Wall, which was used for military lookout and signal transmission in ancient times. For the sake of operational safety, the repair work of the Great Wall in winter has been stopped. I can see that the old Great Wall behind me is unrepaired, the collapse is relatively serious, and the ability to resist natural disasters is weak, so it is necessary to remove danger and strengthen the repair work.

Through preliminary archaeology, the research repair of the Jiankou Great Wall has completed the excavation of Nos. 145, 144, 143 and 142 enemy platforms. The architectural form and engineering practices of the enemy platform were clarified, and cultural relics such as stone tablets, tiles, and weapons of the Ming Dynasty were unearthed, which is helpful to understand the life of the soldiers in the ancient frontier and can provide a design basis for the subsequent repair plan. In the pilot process, Beijing has explored the empirical model of "slowly repairing the Great Wall and researching while repairing" by means of multidisciplinary research, digital tracking records as the guarantee, and protection and display and utilization as the purpose.

Shang Heng, deputy research librarian of the Beijing Institute of Archaeology: At that time, there was no archaeological intervention in some of the Great Wall protection work in Beijing, but only observing the ruins of the Great Wall on the ground, you will find that this approach is actually very one-sided. That is to say, the Great Wall is now a ruin, and we don't know what it was like back then, where the root cause of its disease was, and what its architectural form and craftsmanship were. But with the intervention of archaeological work, we can expose the site as a whole, so that it can be completely renovated and fully displayed in front of the eyes of the planners, so that if we go to build the Great Wall, when we formulate the Great Wall protection plan, our plan can be particularly comprehensive, systematic and scientific, which is also a very important embodiment of the scientific protection of the Great Wall.

In the next step, Beijing will take the research repair project of the Great Wall in recent years as an example, and issue the "Guide to the Archaeological Work of the Protection and Repair Project of the Great Wall of the Ming Dynasty" and the "Manual of the Protection Project of the Great Wall of Masonry and Stone in the Ming Dynasty" and other guiding documents related to the protection of the Great Wall.

(CCTV News Client)