By hannover-web.com CCTV reported that the Great Wall of China, spanning over 2,000 years and thousands of miles, is a masterpiece of ancient beauty and majestic landscapes.
As fall takes hold, the Jiuyanlou section of the Great Wall in Beijing’s Yanqing District showcases its stunning three-color transformation. Stepping into Jiuyanlou, visitors are greeted by the vibrant interplay of golden yellows, fiery reds, and deep greens, with the rugged mountains basking under the autumn sun, giving the Great Wall an even more majestic presence. Jiuyanlou, located at the main peak of Huoyanshan, boasts an elevation of 1,141 meters, marking it as the largest and highest enemy tower along the Great Wall, often referred to as the “First Tower of the Great Wall.”
The Great Wall beautifully embodies the harmony between historical culture and ecological preservation. In recent efforts to protect this unique structure, authorities are shifting from salvage-based conservation to a more research-driven approach, adhering to principles of minimal intervention to preserve the authenticity, integrity, and ancient character of the Wall.
How is the minimal intervention principle applied in the restoration of the Great Wall?
Researchers emphasize that the core principles guiding the restoration of the Great Wall are minimal intervention and authenticity. Taking the Jinshanling section as an example, this portion of the Wall, located in Luanping County of Chengde, was built during the Hongwu period of the Ming Dynasty and stretches 10.5 kilometers. Renowned as the “Essence of the Great Wall,” it features five passes, 67 enemy towers, and three beacon towers, with unique architectural elements that highlight its characteristics.
Jinshanling is particularly celebrated for its well-preserved state. The section has undergone three major renovations, strictly adhering to original designs, craftsmanship, and materials to retain its ancient historical allure and architectural features.
An example of clever conservation can be found in the Jinshan Tower to Yaokou Tower segment, where a wall had begun to lean outwards by approximately 50 meters. Guo Zhongxing, Director of the Jinshanling Cultural Relics Management Center, explained the innovative solutions implemented. “We used a cross steel plate on both sides of the wall, ensuring that the rebar tightened it so that it wouldn’t lean outward any longer.”
Currently, a monitoring project for the actual displacement of the Great Wall has been implemented, with devices installed along over 20 sections to provide real-time data on the structure’s stability.
The approach to Great Wall conservation is evolving from reactive to preventive measures. Guo Zhongxing noted, “Moving forward, we will digitize all sections of Jinshanling, using aerial survey modeling and 3D modeling to provide a more scientifically accurate basis for future protection and restoration efforts.”
The 10.5-kilometer Jinshanling segment encompasses nearly all architectural styles from the Ming Dynasty, representing the essence of the Great Wall. Despite the ravages of time, it remains breathtakingly beautiful.
What modern technologies are being utilized in the preservation of the Great Wall?
At the eastern end of the Great Wall lies Shanhaiguan, the first pass, located in Hebei Province. Among its sections, the three strategic passes of Shanhaiguan are particularly perilous, with the stone Great Wall curling down from cliff tops and climbing steep slopes, creating a dramatic overhang.
During the overall investigation and subsequent protection of the Great Wall, aerial photography technology has played a significant role.
Additionally, the enduring structure of the Wall is subject to the erosion of rainfall. Monitoring data indicates that rain can severely affect earthen sections of the Wall, causing cracks and ultimately leading to collapse. Experts have found that certain algae growing on the soil surface provide significant protective benefits. After screening various types, filamentous blue-green algae were identified as effective in forming biological soil crusts. With careful scientific cultivation in geological laboratories, these algae have now been successfully cultivated on the surfaces of the earthen Wall.
Liu Liang, Director of the Geotechnical Innovation Center at the Eighth Geological Brigade of Hebei Provincial Bureau of Geology and Mineral Resources, explained, “The gray-green biological soil crust effectively prevents rainwater erosion. Filamentous blue-green algae can wrap and entangle with the soil, and their secretion of polysaccharides helps bind soil particles together, creating a protective net structure.”
Furthermore, patrol robots are now capable of independently navigating the Wall’s structure and towers, integrating advanced technologies like 360-degree imaging, laser radar, and infrared monitoring to enhance inspection efficiency and quality.
Liu Liang elaborated on the capabilities of a four-legged robot designed to replace human inspectors. “When it first reaches a location, laser radar can scan the three-dimensional structure. On subsequent visits, we can compare the new data with the previous scan to swiftly identify any areas of concern, such as cracks or structural failure.”
How do we respect the original appearance of the Great Wall while adapting to local conditions in its conservation?
The Great Wall showcases diverse forms, each in varying states of preservation, and our understanding of how to protect it continues to evolve. How should we respect its original appearance with appropriate adaptations?
Liu Wenyuan, Deputy Director of the Cultural Heritage Research Institute of China and the National Cultural Park Protection Institute, highlighted the principle of adapting to local conditions in wall construction. “Different regions use varied materials. To respect the original appearance of the Great Wall, we should implement minimal interventions, striving to disturb as little as possible and to maintain its current state. If a section is well-preserved, we should leave it that way; if it’s damaged, we should work to minimize any new risks. This approach represents our greatest respect for the Great Wall and cultural heritage as a whole.”
