The Forbidden City's Palace Museum will move 130,000 antiquities to an underground warehouse with state-of-the-art temperature, humidity and safety controls, its media office said on Wednesday.
The museum will expand its underground storage space by 8,285 square meters, or 40 percent, in a move to preserve some 1.1 million national treasures.
The expanded underground warehouse will house about 60 percent of all the 1.86 million antiques, museum director Shan Jixiang was quoted by Xinhua News Agency as saying on Wednesday.
After construction is finished in 2020, the museum will gradually remove the above-ground relics underground, Shan said in a statement sent to the Global Times on Wednesday.
The project marks the museum's biggest construction in 20 years, a media representative told the Global Times on Wednesday. She requested anonymity.
The museum was constantly seeking to move its relics underground for better preservation and environmental control, she said via e-mail.
The expansion is part of a program by the Palace Museum to expand and improve underground storage and is scheduled to complete in December 2020, the 600th anniversary of the Forbidden City, the museum said.
Preserving cultural relics has a high environmental requirement including good ventilation, reduced humidity and lower temperatures," Li Mingde, a former vice president of the Beijing Tourism Society, told the Global Times.
"The expansion of underground storage will give museum workers better control of these conditions."
As the former home to the imperial court between 1420 and 1912, the museum has always prioritized protection of culture relics, and "better conservation is for better exhibition," Li said.
In September last year, the museum unveiled the 900-year-old painting A Thousand Li of Rivers and Mountains (Qianli Jiangshan Tu) to the public.
The painting attracted hundreds of visitors on a daily basis. Some even reportedly waited nine hours.
The museum already boasts China's biggest state-of-the-art underground storeroom: waterproof and fireproof since it was built in 1987, Xinhua said.
The museum also established a 13,000-square-meter "hospital" in December 2016, and has the nation's most-advanced conservation studios, according to Xinhua.
In November 2016, the Forbidden City launched its biggest restoration since 1949, after some of the outer wall collapsed in heavy rain.
Museum curator Shan said the 3,437.6 meter wall was suffering from many "diseases," including decaying and crumbling bricks, cracks in the structure and subsidence that were undermining its foundations, The Beijing News reported.
Apart from the wall itself, the repair project also improved the Forbidden City's infrastructure - plumbing, wiring and heating - as it was outmoded and its supply capacity insufficient, the newspaper report said.
