Mu Changyou, a cultural relics restorer of Maiji Mountain Grottoes art institute, performs restoration work of a statue at a cave of the Grottoes in Tianshui City, northwest China's Gansu Province on Dec. 25, 2019. Mu Changyou, 59, has worked on relics restoration for four decades at Maiji Mountain Grottoes, one of the four most famous grottoes in China. Starting as an apprentice, Mu had spent more than 10 years doing chores like cleaning caves, arranging tools, mixing mud and twisting hemp ropes etc. Thanks to constant interactions with and guidance by weathered masters in this walk of life, along with diligence in reading of professional books and hands-on practice, Mu eventually turned himself from a farmer to a senior cultural relics restorer.

Apart from devoting his energy and expertise directly to these relics, Mu is also an ardent mentor, looking to pass all his wisdom on to the young people working around him, and contribute to the sustainability of the Maiji Mountain Grottoes. (Xinhua/Ma Ning)

Mu Changyou, a cultural relics restorer of Maiji Mountain Grottoes art institute, performs restoration work of a statue at a cave of the Grottoes in Tianshui City, northwest China's Gansu Province on Dec. 25, 2019. (Xinhua/Ma Ning)

Mu Changyou (1st R), a cultural relics restorer of Maiji Mountain Grottoes art institute, guides his apprentice at a cave of the Grottoes in Tianshui City, northwest China's Gansu Province on July 16, 2025. (Xinhua/Cai Xiangxin)

Mu Changyou (C) poses for photos with his apprentices after a day's work in front of Maiji Mountain Grottoes art institute, in Tianshui City, northwest China's Gansu Province on July 16, 2025. (Xinhua/Cai Xiangxin)

Mu Changyou, a cultural relics restorer of Maiji Mountain Grottoes art institute, fills out a logbook for restoration work at a cave of the Grottoes in Tianshui City, northwest China's Gansu Province on July 16, 2025. (Xinhua/Chen Bin)

Mu Changyou, a cultural relics restorer of Maiji Mountain Grottoes art institute, checks a statue he restored at the Grottoes in Tianshui City, northwest China's Gansu Province on July 16, 2025. (Xinhua/Chen Bin)

Mu Changyou, a cultural relics restorer of Maiji Mountain Grottoes art institute, checks a statue at a cave of the Grottoes in Tianshui City, northwest China's Gansu Province on July 16, 2025. (Xinhua/Chen Bin)

Mu Changyou, a cultural relics restorer of Maiji Mountain Grottoes art institute, checks a statue at a cave of the Grottoes in Tianshui City, northwest China's Gansu Province on July 16, 2025. (Xinhua/Chen Bin)

Mu Changyou, a cultural relics restorer of Maiji Mountain Grottoes art institute, fills out a logbook for restoration work at a cave of the Grottoes in Tianshui City, northwest China's Gansu Province on July 16, 2025. (Xinhua/Chen Bin)

A drone photo taken on July 16, 2025 shows a partial view of the Maiji Mountain Grottoes in Tianshui City, northwest China's Gansu Province. (Xinhua/Chen Bin)

Mu Changyou, a cultural relics restorer of Maiji Mountain Grottoes art institute, browses through his restoration draft at a cave of the Grottoes in Tianshui City, northwest China's Gansu Province on July 16, 2025. (Xinhua/Cai Xiangxin)

Tourists visit Maiji Mountain Grottoes in Tianshui City, northwest China's Gansu Province on July 16, 2025. (Xinhua/Chen Bin)

Mu Changyou (R), a cultural relics restorer of Maiji Mountain Grottoes art institute, guides his apprentice at a cave of the Grottoes in Tianshui City, northwest China's Gansu Province on July 16, 2025. (Xinhua/Chen Bin)

A drone photo taken on July 16, 2025 shows a view of the Maiji Mountain Grottoes in Tianshui City, northwest China's Gansu Province. (Xinhua/Chen Bin)

Mu Changyou, a cultural relics restorer of Maiji Mountain Grottoes art institute, fills out a logbook for restoration work at a cave of the Grottoes in Tianshui City, northwest China's Gansu Province on July 16, 2025. (Xinhua/Chen Bin)

Mu Changyou (L), a cultural relics restorer of Maiji Mountain Grottoes art institute, guides his apprentice in restoring a statue at a cave of the Grottoes in Tianshui City, northwest China's Gansu Province on July 16, 2025. (Xinhua/Cai Xiangxin)

Mu Changyou (R) and He Ju, cultural relics restorers of Maiji Mountain Grottoes art institute, perform protection and restoration work at a cave of the Maiji Mountain Grottoes in Tianshui City, northwest China's Gansu Province on Nov. 2, 2024. (Xinhua/Chen Bin)

Mu Changyou, a cultural relics restorer of Maiji Mountain Grottoes art institute, fills out a registration form after returning the keys to the Grottoes in Tianshui City, northwest China's Gansu Province on July 16, 2025. (Xinhua/Chen Bin)

Mu Changyou (front), a cultural relics restorer of Maiji Mountain Grottoes art institute, checks statues and murals at a cave of the Grottoes in Tianshui City, northwest China's Gansu Province on July 16, 2025. (Xinhua/Chen Bin)