DUNHUANG, China — Approaching China across the Eurasian continent, one crosses the Tianshan mountains only to be confronted by the mighty Taklamakan Desert, with its sinister epigraph: “If you go in, you won’t come out.” At Kashgar, the Silk Road divides into two branches, skirting the northern and southern hems of the desert.

Parinirvana (Sakyamuni Entering Nirvana), from the altar of the western wall of Cave 158, Mogao Grottoes

For those who survived the trip, the oasis of Dunhuang east of the desert must have been a fine sight indeed. Marco Polo, having journeyed 30 days through the Taklamakan, was one of them.

“The people are for the most part idolaters, but there are also some Nestorian Christians and Saracens,” he wrote of the place in his “Travels.”

Eleven years ago, excavating a meditation cave in the northern part of Dunhuang’s Mogao Grotto complex, archaeologist Peng Jinzhang made an exhilarating discovery: four beautifully preserved pages of white-linen paper filled with a script that he could not identify. Scholars at Beijing University helped him solve the mystery. The language was Syriac, and the pages from the Psalms in the Old Testament. Peng’s find confirms Polo’s observation that Christians did indeed live in Dunhuang.

A donor, the king of Khotan, wall painting from Cave 98 at the Mogao Grottoes, Western Wei Dynasty (535-557)

The Syriac Bible find, announced recently, is only one of several discoveries made by Peng and his team during their six-year excavation. The Mogao Grottoes are a complex of some 750 caves carved out of the face of the sandstone cliff along the Daquan River, 25 km southeast of Dunhuang in China’s Gansu Province.

Among the 243 excavated caves — the monks’ living quarters, meditation and burial chambers — the team found movable wooden types for the Uighur language, unique documents written in the obscure, defunct ‘Phags-pa and Xixia languages, Persian silver coins and countless other artifacts.

Founded in the fourth century, the Buddhist cave temples at Mogao flourished for 1,000 years as a haven for Buddhism, scholarship, meditation and artistic creativity, before being abandoned as the Chinese withdrew their garrisons in 1372 and the maritime route proved more reliable than the Silk Road. In 1900, the priest Wang Yuanlu stumbled upon the famous Hidden Library, where some 50,000 documents, including a copy of the Diamond Sutra that is the oldest known printed book, had lain untouched for 1,000 years.

In 1907, the British-Hungarian archaeologist Sir Aurel Stein arrived in Dunhuang, and, having paid Wang a mere four silver pieces, carted off thousands of manuscripts, silk scroll paintings and wood slips. These are now housed in the British Museum, the British Library and the National Museum in New Delhi.

French, American, Japanese and Russian explorers followed, and by the 1930s what remained at Mogao were some 2,000 Buddhist sculptures and the caves’ stupendous murals, which depict sutras, legends, customs, trade and daily life over a span of 800 years.

Today, the Mogao Grottoes are the mainstay of Dunhuang’s economy, attracting thousands of visitors to this remote outpost at the western end of the Great Wall each year, as well as the locus for an esoteric, thriving field of scholarship. In the ’60s, the eroding face of the cliff was reinforced with an unbecoming but functional concrete facade. In 1987, the Mogao Grottoes were declared a World Heritage site by UNESCO.

For the past decade, an international team of experts — led by the Dunhuang Research Academy in cooperation with Osaka University, the Tokyo National Research Institute for Cultural Properties, the Getty Conservation Institute and other organizations — has been hard at work trying to save the caves’ wondrous paintings with the same passion, creativity and attention to detail as the monks who created them.

A 5-km-long windbreak fence has reduced the amount of sand blown over the cliff face by 60 percent. Iron doors have been installed in all the caves to reduce dust and humidity. Up on the cliff, a solar-powered meteorological station records basic weather data, while substations in selected caves record humidity, temperature and carbon dioxide. To strengthen the caves, scientists are measuring the cracks, and plan to pin and stabilize them.

Other work focuses on documenting the paintings, analyzing the color pigments, understanding the reasons for their deterioration, and developing new materials and techniques to preserve them for posterity.

In Cave 85, a large Tang Dynasty cave with 16 illustrated sutras that has been selected as a model case study, wall-painting conservator Stephen Rickerby is busy testing different grouts — a kind of paste that is to be injected behind the painted mud plaster to secure it to the underlying rock wall.

“For a conservator like me, the Mogao Grottoes are heaven,” says Rickerby. As a temporary measure, until a suitable grout has been devised, Japanese tissue paper is being used to hold the flaking paint in place.

Nearby, a member of the team headed by professor Chikaosa Tanimoto at Osaka University is measuring the underlying rock’s moisture content, while an international group of experts huddle to examine the results of a thermography test, which identifies detachments in the plaster through the measurement of minute differences in temperature.

“These paintings deserve the same kind of attention and preservation as a Rembrandt or a da Vinci, and they are much more threatened than paintings on canvas,” says Dr. Neville Agnew, a conservation scientist from the Getty Conservation Institute.

As Tanimoto, Agnew and their colleagues race against an unforgiving clock to preserve this unique historical record, the thousands of tourists from China and the rest of the world who make their way out to Mogao every year, while bringing much-needed cash to the region, also pose a threat to the health of the paintings. Humidity, together with salt leaching from the underlying rock, is the main culprit in the deterioration and flaking of the murals.

Because of the deleterious effect of too many visitors on the murals, a standard tour of the Mogao Grottoes is now restricted to brief visits to a few, unlit caves — an anticlimactic experience for far travelers who have paid the 66 RMB ($8) entrance fee. The conservationists are presently pondering ways of lighting the murals without causing further damage and devising strategies to give as many people as possible the opportunity to see them. Meanwhile, in the adjacent museum, visitors can contemplate accurate reproductions of several of the caves’ most noteworthy artworks.

While the conservation work being done at the Mogao Grottoes is one of China’s most successful international collaborations in this field, the dispersal of the Hidden Library’s manuscripts around the globe remains a controversial issue.

“From a moral point of view, the artifacts should be returned,” says Dr. Rong Xinjiang, a Dunhuang expert at Beijing University. “The Chinese government should, at the appropriate time, through the appropriate legal and diplomatic channels, try to retrieve the artifacts.”

At the same, however, the dispersal of Cave 17’s treasure around the world has turned Dunhuang studies into a global endeavor, with scholars from many countries laboring in libraries to decipher and interpret the manuscripts, written in rare, dead languages such as Tangut, Tokharian and Runic Turkic, and dealing with a variety of concerns: historical records, Buddhist sutras, Taoist tracts, medical treatises, herbal pharmacopoeias, calendars, astronomical charts, literature, poetry, folk songs and real-estate deals.

The International Dunhuang Project, begun in 1993 at the behest of the British Library, is now making the treasures from the Hidden Library available at the project’s Web site.

In a separate endeavor, the Andrew W. Mellon Foundation is spending some $3 million to reunite a selection of the treasures from Mogao, scattered around the globe from the National Library in Taiwan to the Bibliotheque Nationale in Paris, in cyberspace.

“The database makes the physical location of the manuscripts redundant,” says Susan Whitfield, who heads the IDP.

Publishing houses in Sichuan and Shanghai have projects under way to publish facsimiles of the manuscripts.

It seems that Dunhuang, in the virtual way of our times, is once again playing the role it did 1,000 years ago as a key junction on the Silk Road: a place that brings people from all over the world together, a melting pot for cultures and a bottomless well of inspiration.

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