China's Xixia Imperial Tombs Inscribed as UNESCO World Heritage Site, Backed by Scientific Support

The Xixia Imperial Tombs in northwest China were officially inscribed on the UNESCO World Heritage List on July 11, 2025, during the 47th session of the World Heritage Committee held in Paris. This designation marks China's 60th World Heritage site and underscores the site's exceptional value in understanding the Tangut people, the Xixia Dynasty (Western Xia, 1038–1227), and the formation of China's unified multi-ethnic nation.

The inscription highlights the mausoleum's “outstanding universal value” as vital evidence of a significant chapter in Chinese civilization and a testament to its rich cultural diversity. The expansive site includes nine imperial tombs, 271 identified satellite tombs, northern architectural remains, and remarkably well-preserved ancient flood control infrastructure.

Scientific Backing for Heritage Status:

The successful nomination was significantly bolstered by rigorous scientific research led by the International Centre on Space Technologies for Natural and Cultural Heritage (HIST), a UNESCO Category 2 Centre based in China. HIST provided crucial evidence and technical support through innovative applications of remote sensing, environmental archaeology, data analysis, and deep learning.

Revealing Hidden Structures
Since 2017, Associate Researcher LIU Decheng of HIST has worked closely with the Ningxia Institute of Cultural Relics and Archaeology to uncover previously unknown elements of the Xixia Mausoleum. By analyzing historical satellite imagery, Liu's team systematically mapped the mausoleum's walls and overall layout. This research led to the discovery of numerous unrecorded satellite tombs and, most notably, a large-scale burial complex situated north of Tombs No. 5 and 6. Comparable in size and status to the known imperial tombs, this newly identified complex provided critical archaeological context and directly supported subsequent excavation efforts.

Unearthing Ancient Hydraulic Engineering
In 2024, HIST was entrusted with conducting urgent environmental archaeology investigations focused on ancient hydrology and flood control systems. Liu's team integrated remote sensing, field surveying, paleogeography, geoarchaeology, and Quaternary geology to guide their fieldwork. As a result, they identified a total of 74 ancient flood control structures, including 65 embankments, five dams, and four diversion channels, spanning 7,715 meters. Among these were 31 newly discovered embankments, two new dams, and one new diversion channel, which together contributed an additional 3,538 meters of infrastructure previously undocumented.

Reconstructing Ancient Water Systems
The team also reconstructed the ancient water systems and analyzed how these hydrological features influenced the spatial arrangement of the tombs. Using the MIKE11 hydrological model, they simulated extreme rainfall scenarios from the Xixia period to identify flood-prone zones. This modeling confirmed the functional necessity of the ancient flood control structures and highlighted the scientific and engineering sophistication of Xixia-era hydraulic planning. These findings not only offer new insights into historical water management but also provide a valuable reference for modern heritage conservation practices. The newly discovered hydraulic system will be officially incorporated into the composition of the World Heritage site, and a comprehensive research report is currently in preparation.

Intelligent Mapping and Risk Assessment
In parallel, Associate Researcher LUO Lei and his team at HIST applied multi-source satellite imagery and deep learning to develop a transferable framework for archaeological site detection and assessment. This approach enabled the intelligent mapping of both imperial tombs and satellite tombs, while also revealing significant correlations between the spatial layout of the mausoleum and its surrounding natural environment. Additionally, the team introduced the Helan Mountain Alluvial Fan Index (HALF), a novel metric designed to assess the site's exposure to natural hazards. These contributions substantially enhance the capacity for risk-informed management of the site and provide a robust scientific basis for its long-term preservation.

A Milestone Achievement

HIST delegates present in Paris witnessed the culmination of years of dedicated multidisciplinary research and digital heritage protection efforts. The successful inscription of the Xixia Imperial Tombs stands as a testament to the power of integrating cutting-edge Earth observation technologies and archaeological science.

“This inscription is not just about preserving tombs; it's about unlocking the sophisticated engineering and cultural landscape of the Xixia,” commented a HIST representative at the session. “The technologies applied have revealed hidden chapters of history and provided the concrete evidence needed for global recognition, ensuring this remarkable site is safeguarded for future generations.”

HIST delegates witness the moment of the Xixia Imperial Tombs's inscribtion on the UNESCO World Heritage List during the 47th session of the World Heritage Committee in Paris, France, July 11, 2025. (Image by AIR)