Chengde, a city in north China's Hebei province, began operations to protect the ancient royal resort and the surrounding temples, Guangming Daily reported Monday.

The largest ever project to protect the cultural heritage sites since 1949, with a total budget of over 9.5 billion yuan ($ 1.44 billion), is under way, the newspaper said.

The project is expected to be completed in five years and the central government has reportedly injected 600 million yuan ($ 91 million) to protect the Chengde Summer Resort, of which 520 million yuan will go towards the protection of cultural relics and 80 million yuan will go towards water conservation in the area.

"How we go about protecting the buildings will be the largest problem during the project" Shan Jixiang, the director of the leading panel conducting the protective project, said, adding that because of the unique nature of each building and there is no experience for reference as to how to go about protecting and restoring them.

Chengde Summer Resort, the largest existing royal garden in the world built in the 18th century for the royal family in Qing Dynasty (1936-1911), and its surrounding temples were declared World Cultural Heritage sites in 1994.

By Guo Changdong and Chen Keyu