Mou Changyou, a 55-year old conservator, inspects a damaged Buddha statue in the Maijishan Grottoes in Tianshui, Northwest China’s Gansu province. Photo: Chen Liang/Caixin

The Maijishan Grottoes comprises hundreds of caves cut in the side of a 142 meters’ hill with over 7,000 Buddhist statues that can be traced back to the Northern Wei dynasty (386 A.D. – 534 A.D.). Photo: Chen Liang/Caixin

Mou uses a self-made tool to repair damaged relics in Maijishan. He entered Maijishan Grottoes Art Research Institute in 1985 and has worked on grottoes’ protection for 36 years. Photo: Chen Liang/Caixin

Mou repairs a broken base of a Buddha statue with a colleague in Maijishan Grottoes. He finds it difficult to find and keep a qualified successor. According to authorities, the number of archaeologists who specialize in grottoe relics is less than 30 in China, resulting in a serious talent shortage. Photo: Chen Liang/Caixin

The clay palette Mou uses to adjust color before repairing statues. Photo: Chen Liang/Caixin

Mou examines a restored cave in Maijishan. Photo: Chen Liang/Caixin

A Sakyamuni Huizi statue that represents teachings of lord Buddha is on display in Cave 133 in the Maijishan Grottoes. Photo: Chen Liang/Caixin

Bingling Temple, located in Yongjing county, is another important grottoes site in Gansu. The temple is composed of over 200 caves with more than 800 statutes. Red sandstone consists of the landscape here, making the protection work harder as the soft material is easy to crack when exposed to water. Photo: Chen Liang/Caixin

A cliff sculpture is seen damaged due to water leakage in Anyue county, Southwest China’s Sichuan province. Statistics show that the county contains over 200 valuable carving sculptures. Photo: Ding Gang/Caixin

In one of the caves of Peacock Cave Shrines in Anyue county, the surface of a Majachenmo rock sculpture turned into black as the locals used to cook in there Photo: Ding Gang/Caixin

A headless cliff statue (right) and a Buddha sculpture in which the nose, mouth, lips, and chin were repaired with cement are seen in caves of Anyue county. Photo: Ding Gang/Caixin

A detailed look of the sculpture named Goddess of Mercy With One Thousand Hands, which is located in Dazu Grottoes of southwest China’s Chongqing municipality. Conservators have excluded part of the sculpture from restoration for people to be able to compare when conducting maintenance works. Photo: Ding Gang/Caixin

The sculpture created in the Southern Song dynasty (1127–1279) has been decorated four times over 800 years after its completion. Photo: Ding Gang/Caixin

The tunnel measuring 100 meters long is located behind Cave 125 to Cave 177 in the Dazu Grottoes. The annual rainfall in the Dazu area could reach around 1,000 millimeters, making water control an essential task in protecting the grottoes’ sculptures. Photo: Ding Gang/Caixin

A cliffside statue is located on the Mount Baoding of Dazu county. Cave sculptures in the area are mainly created in Tang and Song dynasties. Photo: Ding Gang/Caixin

Barriers are set at the Baoding Mountain Buddhist site in Chongqing to prevent water damage. Photo: Ding Gang/Caixin

The reclining Buddha sculpture located in Bamiao town of southwest China’s Sichuan province is 21.3 meters in length, which has been listed as a key protection unit in 1988. Photo: Ding Gang/Caixin