During the scorching summer, a team of seven had to wear layers of thick clothes and knee pads to stay warm in a freezing and damp grotto. The dark space is dimly illuminated by their headlights and holds ancient paintings on its walls dating back hundreds of years ago.

They are not adventurers but seven restoratives who help bring back the shine of the artwork in more than 160 Grottoes that dot the red cliffs of Xumishan in Northwest China’s Ningxia Hui Autonomous Region.

The Xumishan Grottoes, firstly built in the late period of the Northern Wei Dynasty (386-534), were adorned with 162 caves and more than 1,000 statues, along a main stretch of the ancient Silk Road.

The Mural Paintings, totalling 185 square meters, are now in dire need of repair due to destructive human behaviours and natural factors such as rock weathering that have occurred over a millennium.

“I got goosebumps when the whole pattern of the painting showed up clearly after we spent 20 some days cleaning it up,” said 60 year old Wang Minquan, an expert in the group participating in a year-long repair program since April, the largest of its kind since the Qing Dynasty (1644-1911).

The work can be tedious and demanding, Wang said, adding that young people these days do not have the patience to climb up and down the scaffolds, fix cracks and clean flaky walls all day.

On some steep rocky slopes, the team has to scramble a few dozen meters to reach a higher stone statue, with ropes tied around their waist like a climber.

Years of work in the freezing and dark grottoes resulted in cervical spondylosis and cold legs for Wang and his colleagues.

To take the chill off their bodies, they usually take a break every two hours to bathe in the sunshine and sip a cup of hot tea. “Over an hour of work in the cave can make one chilled to the bone,” 69 year old Wang Xiaosheng said.

Wang Xirong, 40, Son of Wang Xiaosheng, is the youngest Member of the team. He started his career in his 20s, around the same age his father followed in the steps of his grandfather.

“It was not easy for me to stick to the job at the very beginning as we often spend months or years away from our families, and sometimes it is like living in the wilderness,” said the 40 year old.

Together with his father, Wang has travelled half of the country to repair mural paintings including in the relic-rich Shanxi and Shaanxi provinces, as well as Sichuan after the 2018 earthquake.

“The past decades have polished my edges, as I have been truly impressed by the craftsmanship and patience of ancient artisans who left the treasures for us,” he said.

“Those who make it a lifelong career are those who have a passion for cultural relics and history,” said Wang’s father.

Decades of life “trapped” in grottoes make it hard for the seven experts to keep up with the pace of modern life, but they always update themselves with the latest knowledge on repairing mural paintings. “It’s my dream to repair works for the Mogao Grottoes in Dunhuang, which is heaven for craftsmen like me,” Wang said.