April 28, 2026
BEIJING – In 1929, a young Chinese student named Xi Fuquan stood before a doctoral examination committee at the Technical University of Berlin, Germany.
When they granted him his Doctor of Engineering degree, he became one of the earliest Chinese architects to earn a German doctorate.
For his research, Xi studied three Qing Dynasty (1644-1911) architectural models at the Ethnological Museum of Berlin. They were delicate, intricate, and entirely made of paper. Known as tangyang, these models were once used by Qing court artisans to show emperors what their tombs would look like before a single brick was laid.
Xi examined them closely. He read the tiny Chinese characters written on small yellow slips of paper pasted onto the models. He recorded dimensions, materials, and construction techniques.
“These models themselves are not made entirely to scale, but they provide extremely detailed information about measurements, numbers, terminology, and materials,” he observed.
“That information is written on many yellow slips and pasted onto the corresponding parts of the models. From these slips, it is clear that two of the models were designed for the tombs of Emperor Tongzhi’s consorts.”
Then, for nearly a century, the research had been quiet until five years ago when a new generation of students from both China and Germany picked up where Xi left off.
The objects of their study were the very same ones Xi had examined: two tangyang models of Qing Dynasty imperial underground palaces — one (the mausoleum of an empress) held in the Beijing-based Tsinghua University’s collection, the other (an emperor’s mausoleum, previously misidentified) at the Ethnological Museum of Berlin.
These two models, separated by continents and largely forgotten, became the unlikely bridge connecting young architecture students from the two countries.
In 2021, students from Tsinghua University’s School of Architecture and Technical University of Berlin’s department of architecture and urban history began working side by side across time zones, languages, and cultural backgrounds. They shared research notes, compared scientific data, and exchanged visits.
The Chinese students brought deep knowledge of Qing Dynasty craftsmanship and cultural heritage conservation, while the German students brought fresh eyes, asking unexpected questions about how these paper models compared to Renaissance architectural models from the West.
Pigments and tools used for surface painting. PHOTO: CHINA DAILY
Together, they X-rayed the models to reveal hidden internal structures, and analyzed pigments, papers, and adhesives under microscopes.
They corrected a long-standing misidentification and proved that the Berlin model belonged to the 10th Qing emperor Tongzhi’s Huiling Mausoleum. Previously, the model was considered to be the 11th Qing emperor Guangxu’s Chongling Mausoleum.
Most remarkably, the German students built a full-scale physical replica of the Huiling underground palace tangyang with their own hands, carefully “drawing” each Chinese character on the yellow slips as if they were images.
All of this work — the scientific data, the corrected history, the handmade replica, the cross-cultural friendship — is now on display at the ongoing Dialogue Reproducing Inheritance — A Documentary Exhibition of the Collaborative Research on Tangyang Model Undertaken by Students from China and Germany, which runs at the Prince Kung’s Palace Museum in Beijing until May 5.
The exhibition is divided into four sections — Origin, Exploration, Replication, and Heritage — and documents the full arc of this Sino-German partnership, tracing it to Xi’s dissertation in 1929.
The current exhibition builds directly on a previous showcase held at the Prince Kung’s Palace Museum in September 2025. Titled From Model to Masterpiece: Tracing the Legacy of Ironed Paper Models, the exhibition featured 72 original tangyang alongside six newly crafted models.
While the 2025 exhibition focused on the cultural and design philosophies behind tangyang, the 2026 exhibition shifts the lens to scientific reconstruction and cross-cultural collaboration, told through the eyes of young people.
“Tangyang is a type of architectural model mostly made of paper that was used in ancient China,” explains Lin Yucen, a co-curator of the exhibition and a staff member at the Prince Kung’s Palace Museum. “Other materials such as wood were also used.”
The name comes from the manufacturing process, in which artisans used a hot iron to shape the roof components, hence tang (to iron) and yang (model). Its function was similar to today’s 3D renderings.
“After the artisans finished making it, the rulers could see the form and design of the building,” Lin says.
“It was a medium that transformed abstract concepts, including numbers and drawings, into something tangible that the decision-maker could clearly understand,” he adds.
One of the most delightful details in the exhibition involves those yellow slips — the very same ones Xi described in his dissertation.
On the replica created by the Berlin students, the yellow slips were covered by their handwriting.
“To be honest, their Chinese is probably at a beginner level. But in those somewhat naive brushstrokes, you can actually see their genuine interest in tangyang and in traditional Chinese craftsmanship,” Lin says.
The collaboration also revealed how differently Chinese and German students approached the same object.
Tsinghua University students tend to see tangyang as a cultural relic, while in the eyes of the Berlin students, it is an architectural model, he adds.
Wen Wen, another co-curator of the exhibition and a graduate of Tsinghua University’s School of Architecture, says tangyang is a relatively niche field, both in China and Germany.
“So for most students, it was something new and interesting. They were genuinely curious,” she notes.
The German side had the original tangyang models, but they lacked the capacity for in-depth research.
“Before we got involved, they had done basic documentation, but no deeper research. After Xi Fuquan, very little had been done,” Wen points out.
An interactive activity at the exhibition. PHOTO: CHINA DAILY
Tsinghua University, on the other hand, had been systematically documenting and analyzing its own tangyang collection since 2019.
“We used a range of scientific methods, and took X-rays to see the internal support structures. We used microscopic cross-section analysis and polarized light microscopy to analyze pigments, paper types, adhesives, and craftsmanship,” Wen says.
These techniques were applied to the Berlin museum’s tangyang models, with some limitations, because the models couldn’t be moved.
Still, the collaboration opened new doors.
“It’s fair to say that through this project, many German students learned that tangyang is a field worth studying,” Wen says. Both sides are now discussing deeper, long-term cooperation.
The exhibition itself is unusual in that it was almost entirely created by young people.
“In this exhibition hall, we have a curation approach called ‘My Space, Your Rules’,” says Lin, the co-curator.
The curatorial team has an average age under 30. It includes junior staff members from the Prince Kung’s Palace Museum, students from Tsinghua University, and students from the Technical University of Berlin.
Handwritten notes, hand-drawn illustrations, Q&A boards, and video interviews fill the rooms, reflecting a youthful lightness that nicely balances out the profundity behind the cultural relic’s weight. Walking through the exhibition feels like stepping into a university classroom during a lively presentation.
“We wanted to show how young people today, especially young people from different countries, look at tangyang,” Lin says.
When asked about why tangyang should be studied at all in the 21st century, when there is much more advanced modeling software and drawings, Wen emphasizes that tangyang still holds value in two distinct ways.
“First, it is a cultural relic. It records certain social and historical conditions of its time, so it’s worth studying like any other artifact,” she says.
Additionally, she considers it a window into ancient Chinese architectural design.
“What we’re really doing is using tangyang to see how ancient people built houses, how they designed buildings, and how the people behind these structures lived and spent their days,” she says.