Since the 1920s, the “Kneeling Attendant Bodhisattva,” a 1.2 meter-tall praying figurine, has sat behind glass at the Harvard Art Museums. Over 10,000 kilometers away, in a cave carved into a sandy cliff in China’s arid northwestern Gansu province, a patch of bare stone is a reminder that the statue did not always belong in Massachusetts.

That cave — Cave 328 — is one of almost 500 that form the Mogao Grottoes, a UNESCO World Heritage Site lying around 30 kilometers from the city of Dunhuang. The cliff is famous for its exquisite murals and sculptures created by Buddhist artists over a period stretching from the fourth to 14th centuries.

Cave 328’s absent inhabitant — one among many Mogao relics that are housed in other countries, including France, the U.K., and India — is now the target of a China-led project to unify the contents of the grottoes. The project doesn’t aim to demand that Harvard return what its then-curator of art Langdon Warner took from the cave in 1924, but to use advanced mapping technology to create precise 3-D renderings of the grottoes in their entirety.

The project, called “Digital Dunhuang,” is China’s attempt to permanently preserve the entire contents of the Mogao Grottoes so that they might serve both scientific research and public enjoyment. Institutions around the world have embarked on similar digitization projects, but the latest China-led endeavor is the only one to attempt to record and archive, in three dimensions, all the items housed in the grottoes. Other projects, like the British Library-led International Dunhuang Project, have tackled artifacts based outside of China, with a focus on the two-dimensional scanning of the manuscripts that the grottoes once held.

For almost half a century, those involved in the management of the grottoes have been more preoccupied with the problem of maintenance than the question of reunification.

At the turn of the 20th century, the grottoes were in a desolate state. In the caves that hadn’t been buried by sand blown in from the surrounding desert, statues decayed and murals flaked. The situation was not helped when, following Russia’s October Revolution in 1917, troops loyal to the czar fled across the border and set up camp at the Mogao Grottoes. Soldiers burned fires and cooked inside the caves, even wantonly scratching murals and breaking limbs from statues.

Efforts since to return the Mogao Grottoes to their former glory have captivated the cultural pride of generations — in fact, many use the term “Mogao spirit” to describe the dedication of those who have devoted themselves to the caves’ restoration.

Wang Xudong doesn’t like the way the term is sometimes used. Wang is the director of the Dunhuang Academy, the organization charged with protecting the grottoes and leading the recent efforts to digitize their contents. “The reason so many people come, stay, and work here is not because they are noble saints,” Wang told Sixth Tone. “Rather, it’s just that Mogao is so unique and marvelous.”

The allure of the grottoes was too much for Wu Jian, who joined the academy when he was just 18 back in 1981. Then a photographer, Wu now heads the academy’s Cultural Relics Digitization Institute, the headquarters for the Digital Dunhuang project. Attempts to visually document the contents of the caves began in 1993, Wu said, when his team began preserving the grottoes’ contents by taking photos, which were later scanned and archived.

With the advent of the digital camera, however, Wu and his team found that the material they’d collected paled in comparison with what digital technology could provide. “The information we collected in those years is now out of date,” Wu said. “But I guess that’s the price we have to pay for being pioneers.”

Following the adoption of digital technology, work on preserving the grottoes took a new direction in 2006 with the founding of the Cultural Relics Digitization Institute. Within three years, Wu said, he and his team of a dozen or so people — the center now has 80 employees — had mastered the technology needed for two-dimensional digitization.

The team has now completed photographing the murals of more than 120 caves, with an average-sized mural requiring 1,000 high-resolution photographs. The amount of time required to stitch the images together gives a sense of the complexity of the task; one mural can take an individual technician up to 50 days to piece together.

Yet the real challenge for the Digital Dunhuang project lies not with the murals but with the mapping of the caves’ three-dimensional inhabitants. After years of experimenting and failed collaborative efforts with other research bodies, in 2011 the academy lucked upon a small technology company that happened to be building advanced 3-D mapping technology. Based on the other side of the country in Shanghai, the outfit of just a dozen employees had developed technology that could produce incredibly accurate 3-D renderings from the data of thousands of high-resolution images.

By the end of 2015, the company — Shanghai Haohan Digital Technology Co. Ltd — had completed the 3-D scanning of the 13 sculptures in Caves 45 and 332. The beginning of 2016 saw them complete the digitization of Cave 328’s contents — minus its U.S.-based absentee.

The company’s technical director, Hu Zhuomin, is hopeful that the project will secure the opportunity to visit Harvard and conduct an on-site 3-D rendering of Cave 328’s missing statue.

“As the commissioned party, I know I am in no position to consider — let alone initiate — such a move,” Hu told Sixth Tone. “Yet I think every Chinese person would support it.” For many people, wrapped up with the notion of the “Mogao spirit” is a deep sense of pride in the site and a subsequent resentment for the fact that so many of the site’s contents have been relocated to foreign locations.

In fact, this is a move that those at the academy have already begun contemplating. “We finally have the ability to do what we Chinese have always wanted to do,” director Wang said, referring to the fact that the unification of the grottoes’ contents is now just a matter of clicking a camera shutter, albeit several thousand times.

When it comes to negotiating with Harvard, Wang told Sixth Tone that instead of adopting a “You have to give us what you owe” approach, they intend to be diplomatic. “I will tell them, ‘The relics of the Mogao Grottoes don’t belong to us, nor to China, but to the whole world. So let’s work together to restore our shared cultural treasures to the way they should be.’”

For now, Wang is happy just to test the waters, consulting with academic faculty at Harvard whom he said have been responsive to his inquiries about the possibility of accessing the relics housed at the university. Along with the “Kneeling Attendant Bodhisattva” are a number of murals that were removed from the caves by Langdon Warner at the same time.

While the Harvard Art Museums say they have not received an official request from the Dunhuang Academy, they told Sixth Tone that they would in theory be open to requests to access the statue for scanning. “It is intrinsic to make our collections accessible to students, scholars, and the public, whether through visits to our facility … or via digital platforms,” a spokesperson for the museums said.

Concerns about the condition of the extremely fragile sculpture and the amount of time that it would need to be taken off display for the scanning process would both be taken into consideration, the spokesperson said.

Last year, the National Library of France gave Chinese scholars at the Dunhuang Academy access to the digitized versions of its own collection of Mogao manuscripts. It marked the first time that a foreign institution had given a Chinese body the authority to view such data, something that Wang hopes will set a precedent.

“The problem is that not every foreign institution is as friendly as the National Library of France,” Wang said, referring to the fact that the academy has been turned down previously by other museums, including one prominent London-based institution.

Characteristically low-key, Wang said that he does not intend to seek help from the Chinese government should the project encounter further resistance. He did, however, remark that “the better the relations between China and a certain country, the more willing organizations in that country will be to cooperate.”

Additional reporting by Owen Churchill.

(Header image: Workers hired by Langdon Warner pose for a picture with ‘Kneeling Attendant Bodhisattva’ after they moved it out of Cave 328 in Dunhuang, Gansu province, 1924. Courtesy of the Dunhuang Academy)