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A protective project launch ceremony was held in Yungang Grottoes, one of the four great grottoes in China in Datong, Shanxi province, on June 27. The project aims to reinforce the rock mass and to build the grotto eaves in Wuhua Cave.

It is another large protection work on the cultural relics after the environmental push on the surroundings of the grottoes, marking a new historical period in Yungang Grottoes protection.

Yungang Grottoes is one of the cave groups with the biggest and earliest digging history in China, and is also a world famous culture and treasure collection. Owing to geographic and historical reasons, Yungang Grottoes has long suffered from water erosion and weathering.

Since the foundation of the People's Republic of China in 1949, several protection projects have been performed, but the main problems, including water erosion, have not been solved completely. From 2010 to 2012, the Yungang Grottoes Research Institute has come up with a series of protection plans, hence starting a new protection plan for the grottoes.

The grotto eaves are expected to prevent rain from cave walls, and stabilize temperature and humidity in the cave and reduce erosion of the stone carvings.

The project has gained support from the State Cultural Relics Bureau.