DUNHUANG, China - Starting about 1,700 years ago, deep in the Gobi Desert, monks and merchants began to carve caves into the sides of cliffs. The spectacular caves they made and decorated have survived countless dangers over the centuries: earthquakes and floods, thieving foreign explorers, and Russian soldiers, who cooked over smoky fires in the caves during the 1920s.

Today the caves are facing a new source of danger: modern tourists. With bulky backpacks and hot, humid breath, the tourists represent a real threat to the Mogao Grottoes in northwestern China.

The paintings in the caves are a window into life on the Silk Road, the extensive trade routes that connected Europe and Asia. They are victims of their own popularity.

The grottoes, or small caves, received 26,000 visitors in 1979, the first year they were open to the public. This year, up to 1 million tourists are expected.

Priceless Paintings And Documents

To preserve the caves and paintings, Chinese experts at the Dunhuang Academy partnered with the Getty Conservation Institute in Los Angeles. The two groups have put a long-term plan in place to protect the treasures of Mogao and also introduce them to a wider international audience.

A $50 million visitor center opened this month. Its futuristic shape resembles the sand dunes of the surrounding landscape. The visitor center, designed by Beijing architect Cui Kai, features two theaters that show films which will help visitors understand the caves better. The films also limit the amount the time tourists spend in the actual caves themselves.

Most of the visitors to the site today are tourists from within China. To introduce the caves to a wider international audience, the Getty Museum in Los Angeles will host a major exhibition about the grottoes in May 2016.

The caves hold priceless paintings, but also much more. There's a library of Buddhist religious documents and also non-religious documents in languages including Chinese, Tibetan, Uighur and Khotanese.

The Getty Conservation Institute was founded in 1985. Since then its researchers have worked on many high-profile World Heritage Sites, including the Tomb of Queen Nefertari and the Great Sphinx in Egypt. A World Heritage Site is a place that is listed by the United Nations Educational, Scientific and Cultural Organization as having cultural or natural importance. Getty's scientists have been working with the Dunhuang Academy for 25 years, making it the institution's longest-running project.

At Cave No 85

The Getty's work in China is "some of the best work we've ever done in the field," said Tim Whalen, director of the Getty Conservation Institute.

The conservationists at the Getty have been working to conserve, or protect, the caves. The first step is to survey the caves, to examine them carefully and understand the materials used to make the paintings. Then the scientists can determine the threats - like damage from sand and high humidity.

Neville Agnew, the Getty's expert on caves, has been visiting Dunhuang since the late 1980s - more than 50 times overall. He's seen the area change from an isolated location with no modern airport to a place that may attract 1 million people this year.

China has experienced sharp, fast growth in its economy. The economic boom has made many more people rich and given them enough money to travel to places like the Mogao Grottoes.

"You didn't need to stretch your imagination much to see what might happen in the future," Agnew said.

At Mogao, the Getty team developed a detailed plan to conserve the caves and monitor the conditions there. The plan has been tried over the last decade at Cave No. 85, as a demonstration project.

A Sport Called "Elephant Lifting"

The paintings in the caves are a rich collection of Buddhist art illustrating stories important to the religion. But their significance isn't only religious. They also are important sources of historical information from the times they were painted.

Researchers have used the paintings to learn about ancient Chinese clothing, dance, musical instruments, wrestling, polo, archery and even a sport known as "elephant lifting."

The caves also contain many religious sculptures, including a 1,300-year-old Buddha dressed in orange robes that is more than 100 feet high and nearly 40 feet wide.

Cave No. 85 may be receiving special attention, but a bigger plan was also needed. Getty experts worked with the Chinese and Australian governments to write the China Principles - national guidelines for conserving and managing important historic sites.

China has many historic sites, but managing them was not consistent. The China Principles filled a key gap.

At Mogao, the teams tried to calculate just how many sightseers the cave complex could handle each day.

"These are questions facing World Heritage Sites everywhere - how do you preserve them and still ensure access for the public and scholars?" Whalen said.

The History Of The Silk Road

According to the research by Getty and the Dunhuang Academy, the site could only handle 3,000 tourists a day. That number seemed unrealistically low given the growing interest in the grottoes. Today, the tourist limit has grown to 6,000 tourists thanks to the films. The new visitor center shows two films lasting 20 minutes each.

One film introduces the history of Dunhuang and the Silk Road. The other, projected on a dome-like screen, immerses visitors in the cave paintings, soaring over scenes of concerts, village life, and dancing angel-like spirits called apsaras.

The films address two issues: A way to protect the caves by giving tourists other interesting things to do at the site, and a reason to digitize the cave paintings for research and to showcase them.

The slow and painstaking process of photographing every inch of seven caves took seven months. It took two more years to complete the films.

Now, visitors start by watching the films, before being bused to the grottoes, where they can visit eight to 10 caves.

"Ideally, these methods can be adapted at other sites, both in China and elsewhere in the world," said Wang Xudong of the Dunhuang Academy.]]>