The spirit of continuity, which spans the generations who protect the caves, remains evident, report Fang Aiqing, Wang Kaihao in Dunhuang, Gansu province, and Ma Jingna in Lanzhou.

It's a race against time, as generations of cultural heritage conservators at the Dunhuang Academy endeavor to protect the artistic charm of the Mogao Caves, a UNESCO World Heritage Site, despite erosion by sand and wind.

Restorer Li Bo is a member of the team that is dedicated to protecting the 45,000 square meters of murals and more than 2,400 painted sculptures of the 735 caves of the site, the construction of which spans a millennium, from the 4th century to the 14th century.

Located in the far west of Northwest China's Gansu province, the city of Dunhuang and its neighboring areas — home to the Mogao Caves and other historical monuments witnessing the apex of the ancient, prosperous Silk Road — just unrolled a saga testifying to communication among civilizations across Eurasia.

While characters on the ancient murals refer to Buddha for the truth of life and the universe — a frequent theme of the murals — Li's pilgrimage to enlightenment is reflected in every moment of him sitting in front of the wall and reviving the revelations in the murals with meticulous hand movements, bit by bit, from dawn to dusk, day after day.

A sophisticated mural restorer like Li, who has spent more than 30 years in the business, can only restore an area about the size of a sheet of paper each day.

The past three decades have seen him repair around 1,500 square meters of murals and more than 300 sculptures — the small ones are only about 20 centimeters tall, while the largest reach more than 20 meters in height.

The years have also brought him the exclusive joy of holding a silent dialogue with the mural characters every working day.

In front of a 10th-century mural featuring a mass audience listening to the Buddha at the Yulin Caves in Guazhou county, around two hours' drive from the Mogao Caves, Li mimicked the facial expressions of the characters when introducing his routine work.