"Seeing him lead such a difficult life for so long without showing any regret, I realize there must be something special about his post," said Meng. "He cannot sleep well at home now, as he is always worried his temporary replacement may not take good care of his 'baby'."

Weather and natural disasters are other threats to the relics.

In the second half of last year, heavy rains lashed Shanxi for nearly a month. Although there was no flooding on the mountain cliff, the moisture and torrential rains gave Feng many a sleepless night, as he did all he could to ensure the relics remained safe.

Five years ago, Feng was given a national honorary title as "guardian angel of cultural relics" for his contribution toward safeguarding the treasures. "There must be hundreds of such guards of cultural relics in the province alone, not to mention nationwide," Feng said.

"They are the unsung heroes who are taking care of the nation's cultural and historical heritage, so that future generations can still appreciate their beauty."

Feng was happy that the living condition in the temple has become much better over time. Cameras have been installed at the temple and linked to local public security stations. Once he retires, in 2024, someone else will fill his post. "This is like a relay race. I can honestly say that I have tried my best to do my bit," said Feng.