The Palace Museum, historically and artistically one of the most comprehensive Chinese museums, was established on the foundation of the palace that was the ritual center of two dynasties, the Ming and the Qing, and their collections of treasures. Designated by the State Council as one of China's foremost protected monuments in 1961, the Palace Museum was also made a UNESCO World Heritage site in 1987. 
    Situated at the heart of Beijing, the Palace Museum is approached through Tiananmen Gate. Immediately to the north of the Palace Museum is Prospect Hill (also called Coal Hill), while on the east and west are Wangfujing and Zhongnanhai neighborhoods. It is a location endowed with cosmic significance by ancient China's astronomers. Correlating the emperor's abode, which they considered the pivot of the terrestrial world, with the Pole Star (Ziweiyuan), which they believed to be at the center of the heavens, they called the palace The Purple Forbidden City. The Palace Museum was built from 1406 to 1420 by the third Ming emperor Yongle who upon usurping the throne, determined to move his capital north from Nanjing to Beijing. In 1911, the Qing Dynasty fell to the republican revolutionaries. The last emperor, Puyi, continued to live in the palace after his abdication until he was expelled in 1924. Twenty-four emperors lived and ruled from this palace during this 500-year span. 
    The Palace Museum is surrounded by 10-metre high walls and a 52-metre wide moat. Measuring 961 meters from north to south and 753 meters from east to west, it covers an area of 720,000 square meters. Each of the four sides is pierced by a gate, the Meridian Gate (Wu men) on the south and the Gate of Spiritual Valor (Shenwu men) on the north being used as the entrance and exit by tourists today. Once inside, visitors will see a succession of halls and palaces spreading out on either side of an invisible central axis. It is a magnificent sight, the buildings' glowing yellow roofs against vermilion walls, not to mention their painted ridges and carved beams, all contributing to the sumptuous effect. 
    Known as the Outer Court, the southern portion of the Palace Museum centers on the halls of Supreme Harmony, Central Harmony, and Preserving Harmony. These are flanked by the halls of Literary Glory and Military Eminence. It was here that the emperor held court and conducted his grand audiences. 
    Mirroring this arrangement is the Inner Court at the northern end of the Palace Museum, with the Palace of Heavenly Purity, the Hall of Union, and the Palace of Earthly Tranquility straddling the central axis, surrounded by the Six Palaces of the East and West and the Imperial Garden to the north. Other major buildings include the halls for Worshipping Ancestors and of Imperial Splendor on the east, and the Hall of Mental Cultivation, the Pavilion of the Rain of Flowers and the Palace of Benevolent Tranquility on the west. These contain not only the residences of the emperor and his empress, consorts and concubines but also the venues for religious rites and administrative activities. 
    In total, the buildings of the two courts account for an area of some 163,000 square meters. These were laid out precisely in accordance with a code of architectural hierarchy, which designated specific features to reflect the paramount authority and status of the emperor. No ordinary mortal would have been allowed or even dared to come within close proximity of these buildings.