Costumes and props of Peking Opera are displayed in the newly renovated theater. Zhang Zixuan / China Daily

Apart from the theater stage and Yile Hall, 22 buildings have been reconstructed, while retaining the original shape and value.

The paintings on the buildings' exterior eaves have been repainted.

The interior silk wallpaper has been recovered. And the hanging tablets, inscribed with words, have been restored.

Five special projects were also accomplished, namely three-dimensional laser scan, acoustic testing, theater deformation monitoring, construction process and historical changes, and imperial opera culture.

The three-dimensional scan is capable of calculating the theater's 12 major pressure points, which are facilitated with testing instruments and data-sensing devices to protect the theater from natural disasters such as extreme weather and earthquake.

The latest restoration work also turned part of the dressing hall behind the theater stage into a museum.

The first exhibition is Empress Dowager Cixi and the Peking Opera Cultural Heritage, which runs until July 25.

The exhibition features 128 Peking Opera-related objects from the Palace Museum, the Summer Palace, the Central Academy of Fine Arts, the National Library and the China First History Archives.

The 67 exhibits from the Palace Museum are mainly costumes, props and long-playing records, some of which trace back to as early as the Emperor Qianlong (1711-99). The costumes are sewn with gold thread, dazzling still after more than a century.

"The theater stage will surely add spiritual elements to the Summer Palace," comments Liu Zhen, director of Opera Research Institute, Chinese Academy of Cultural Heritage.