The Hall of the Supreme Principle (simplified Chinese: 太极殿; traditional Chinese: 太極殿; pinyin: Tàijídiàn), also known as Taiji Hall, is one of the Six Western Palaces in the inner court of the Forbidden City.[1] It is situated west of the Palace of Eternal Longevity, north of the Palace of Eternal Spring, and south of the Hall of Mental Cultivation.