Visitors take in the Dunhuang on the Silk Road exhibition in Beijing in April. It featured 3-D printed replicas of Buddha statues from the Mogao Grottoes in Dunhuang, Gansu province.[Photo/Xinhua]

About 2,000 kilometers from the Yungang Grottoes, a 1,500-year-old UNESCO World Heritage site in Shanxi province, a small army of 3-D printers has been working around the clock to save a cultural heritage from oblivion.

Over the past five months, the 20 machines, housed at a workshop in Shenzhen, Guangdong province, have been cranking out full-size replicas of three of the grottoes' Buddha statues. Faithful copies will soon be displayed in the eastern coastal city of Qingdao.

The grottoes contain more than 51,000 statues. But the original works, which were carved into soft stone, will gradually disappear as erosion runs its inexorable course.

"Even today, scientists are unable to stop the aging of the grottoes using chemical or physical methods," said Li Zhirong, an associate professor of archaeology at Zhejiang University who is dedicated to cultural heritage. "Therefore, the best way to protect the grottoes is to preserve their information in a scientific, comprehensive and authentic way."