Hall of Celestial and Terrestrial Union
Jiaotaidian, the Hall of Celestial and Terrestrial Union, was first built in 1420 and rebuilt in 1655 and 1798 respectively. It indicates the emperor and the empress have a nice marriage. It looks like Zhonghedian, the Hall of Central Harmony in shape and is the smallest among the three main palaces in the Inner Court. Usually empresses would receive formal birthday greetings here. Empresses would inspect preparations before they went to preside over memorial ceremonies for Silkworm God and practise sericulture. Emperor Shunzhi's order that eunuchs should be banned to attend to state affairs was placed here. To the right of the throne, visitors will see ancient Chinese water pot - equivalent of sandglass and to the left there is a chime clock. The two timers used to be the reference of the DrumTower and the BellTower.
In addition, the palace also holds 25 imperial seals. Since Emperor Qianlong hoped that the Qing dynasty could last 25 reigns to exceed the East Zhou dynasty, the longest dynasty in China. However history disappointed him, the Qing dynasty only lasted ten reigns.