The Palace Museum starts official renovation on the Hall of Mental Cultivation in the Forbidden City today, a building where emperors of the Qing Dynasty (1644-1911) resided and handled state affairs, according to china.cnr.cn.

Yangxin Dian, or the Hall of Mental Cultivation, is one of the most intriguing palaces in the Forbidden City. Starting in the Yongzheng period, Yangxin Dian was a political decision-making center in the Qing Dynasty and the residence of eight Qing emperors.

The palace had been closed two years and eight months before the official renovation started. According to museum curator Shan Jixiang, during this period the museum had conducted systematic training with 275 craftsmen, covering detailed skills for ancient architecture construction and traditional repairing techniques. 116 craftsmen passed the selection test, and serve as the main force for the renovation of Yangxin Dian.

The research protection project of Yangxin Dian, which features research into the maintenance process itself, is the first attempt by the Palace Museum to practice ancient architecture repair. According to Shan, the previous maintenance projects were mostly rescue repair, which can damage the relics. Shan also revealed from now on, the 1,200 ancient architecture sites in the Forbidden City will be all maintained in a protective fashion.

The renovation of Yangxin Dian is part of an overall renovation project of the Palace Museum, the largest scale since 1911. It is scheduled to finish in 2020 when the Forbidden City welcomes its 600th birthday. There will be no grand ceremonies — only more exhibitions, open areas and activities for visitors to participate then, Shan said.