An ancient hall at the Summer Palace first constructed during the reign of Emperor Qianlong (1736-96) has been restored to its former glory, it was announced at a news conference in Beijing on Monday.

The yearlong restoration took place on Jingfu Ge (Hall of Utmost Blessing), which is located at the east ridge of Wanshou Mountain in the Summer Palace in Beijing.

The restoration of the building is the first of its kind since 1949 when New China was founded.

The project covered its main hall and surrounding courtyard, including repairing the indoor floor and walls, consolidating wooden structures and removing rotten wood, and restoring the ground in the courtyard.

The hall was a two-story pavilion when it was built during the Qing Dynasty (1644-1911), and then known as Tanhua Pavilion, but it was badly burned by Anglo-French forces in 1860. It was rebuilt in 1891-93, during the reign of Emperor Guangxu (1875-1908).

Historical records show Empress Dowager Cixi (1835-1908) received foreign envoys and welcomed their family members in the building, which was not far from her residence in the Summer Palace.

Rong Hua, head of the department of ancient architecture projects at the Summer Palace, stressed the principle of minimizing interference with the building and not changing its original facade during restoration.

"The restoration was to preserve and pass on the historical information and other values of this building in a true and comprehensive way, so that as an old building, its life span can be extended. We don't aim to make it look young again," said Rong.

"The colorful painting decorations on the beams have been kept without any changes," said Rong. "They have been preserved well. Therefore, based on our minimizing interference principle we didn't do anything to them."

In 2017, the heritage monitoring center at the Summer Palace found problems with the building. It had decayed wooden components, loose joints, detached tiles and water damage.

Technicians inspected and monitored the hall four times a year, tracing and recording damage until its official restoration.

"The interior finishes have been preserved well. We have identified the materials of each wooden component and the patterns on them, and recorded the information in a systematic way. That will provide a good reference for possible future restoration," said Rong.

Digital measures have also been introduced to create a three-dimensional image of this building.

Tourists had the opportunity to experience some ancient architectural techniques with their own hands at the site on Monday, an open day for the public to view the restoration.

Visitors experienced tangla, the act of polishing a wood surface with melted wax, as a way to protect wooden furniture.

Shen Wei, a technician on the restoration, said the technique dates back to before the Qin Dynasty (221-206 BC).

The fence around the building installed for restoration will be dismantled in January, and the scenic area will be opened to the public, according to staff at the Summer Palace.