Before the elevation plan was decided upon, experts had proposed two other options for the site. One was to build a dike to separate the palace site from water in the reservoir.

"But the plan was turned down as the site would have been under constant threat from water. Besides, water could have seeped through the dike and damaged the remaining buildings," Shu said.

The other rejected plan called for destroying the current remaining buildings and rebuilding them in their original styles.

"The current plan is the most costly and difficult, but it can best protect the cultural relics," Shu said.

A crucial job for the project is to build new foundations for the existing buildings so the new foundations can serve as platforms that can be raised by jacks underneath them, Dai said.

To protect the buildings from possible damage during elevation, all buildings were reinforced, and the workers will put grout in the new foundation whenever a building is raised 1.5 meters, Dai said.

"Elevating the buildings, the heaviest one weighing more than 4,000 tons, to the equivalent of five floors above their original positions is a huge challenge for us," Dai said.

Wu Hai, a visitor from Wuhan, likes the plan.

"Wudang Mountains are sacred, and I think the world heritage site should be protected," Wu said.

But not everyone agrees.

"It is right to protect cultural relics, but spending 200 million yuan is too expensive, and the amount could have been used to improve the livelihood of the local people," said Yan Chao, a student studying German in Huazhong University of Science and Technology.

This is not the first time in China old buildings have been raised to protect them.

A palace in Nanjing Museum that weighs 7,700 tons was raised 3 meters in 2010 in Nanjing, East China's Jiangsu province.

Gu Xiaochi in Wuhan contributed to this story.

wangxiaodong@chinadaily.com.cn