The Yungang Grottoes in Datong, Shanxi province, are a UNESCO World Cultural Heritage site. Existing for nearly 1,600 years, the caves are deemed "history engraved on stones" by Hang Kan, director of the Yungang Research Institute, formerly known as the Yungang Grottoes Research Institute.

"We must protect, study, present and pass the history down to future generations," Hang is quoted as telling Shanxi Daily. Hang says the team is enlarging the range of protection and delving into the details by applying more scientific methods and advanced technology.