Repairers restore the wall paintings in 27-meters-high Cave 130, the second biggest cave among Mogao Grottoes's 735 caves. The more than 1,000-year old ‪‎Mogao Grottoes‬ in Dunhuang, Gansu Province in China is a ‪World Cultural Heritage‬ recognized by UNESCO. Each cave has ‪‎Buddha‬ statues and wall paintings illustrating the lives and religions of people in different dynasties. It carries crucial historical and cultural value, but due to old age and changing weather, it suffers from different levels of deterioration. Repairing such works requires scientific and very skilled techniques and long years of dedication. Sometimes restoring a cave can take nearly 10 years. Photos: Li Jingjing /GT