The restoration has begun in the Mati Temple Grottoes, a national key cultural relic protection site and major landmark in Zhangye City, northwest China's Gansu Province, according to local authorities.

The repair work is focused on one of the site's major attractions, the Thousand Buddha Caves, which is a group of eight caves, said Yao Guilan, director of the Institute for Cultural Heritage Preservation in Zhangye.

According to Yao, cracks have appeared in rocks due to a damp environment and there are areas marred by water seepage.

Six of the eight caves will undergo restoration, said Yao, adding that the work includes consolidating the rock mass and improving water drainage system on the roof.

The project is expected to be completed by February 2022.

First built around 1,600 years ago along the route of the ancient Silk Road, the Mati Temple Grottoes are famous for Buddhist relics, including more than 500 colored sculptures as well as murals spanning a total of over 1,200 square meters.

To better preserve the site, a digitalization project started in June, and an archaeological investigation involving researchers at home and abroad is also underway, according to Yao.

(With input from Xinhua)