Construction began in 1406 under the Yongle Emperor, who had seized the throne from his nephew and needed a capital to match his ambitions. Over a million laborers worked for fourteen years, quarrying marble from Fangshan 70 kilometers away, floating massive timbers down rivers from forests in southwestern China, and firing the distinctive golden bricks that line the palace floors. The layout copies the cosmic order: a north-south central axis aligns the most important halls in sequence, while the Outer Court handled affairs of state and the Inner Court sheltered the emperor's private life. Every dimension carried meaning. The Hall of Supreme Harmony, the largest structure in the complex, is nine bays wide and five bays deep -- nine and five being numbers symbolically reserved for the emperor alone.

Life inside the Forbidden City operated by rules that seem alien to the modern world. At its peak, the palace housed the emperor, his empress and consorts, thousands of eunuchs who served as the only men besides the emperor allowed to stay overnight, and a vast staff of maids, guards, and officials. A system of 308 gilded water vats -- kept heated in winter to prevent freezing -- stood ready against the constant threat of fire, which nonetheless destroyed major buildings seven times. The palace survived something worse than fire in the twentieth century: revolution. When the last emperor, Puyi, was expelled in 1924, he had already been living as a figurehead in the Inner Court for over a decade while the Republic governed from outside. He reportedly rode a bicycle through the ancient halls.

The Palace Museum opened in 1925, inheriting the imperial collections that had been accumulating since the fifteenth century. What visitors see today represents only part of what once filled these halls. During the Second Sino-Japanese War, museum staff packed nearly 20,000 crates of artifacts and moved them across China in a remarkable odyssey of preservation, shifting the collection through multiple cities over more than a decade to keep it from Japanese forces. After the Chinese Civil War, the Nationalist government transported a portion of the collection to Taiwan, where it now forms the core of the National Palace Museum in Taipei. The Beijing collection still holds approximately 1.86 million artifacts, including paintings, ceramics, jade carvings, and bronze pieces spanning millennia of Chinese civilization.

From above, the Forbidden City reads like a textbook on Chinese imperial cosmology. The complex sits along a precise north-south axis that extends through Tiananmen Gate to the south and Jingshan Hill to the north, where the earth excavated from the palace moat was piled into an artificial mountain. Golden-glazed roof tiles -- a color exclusively reserved for the emperor -- create a sea of ochre that contrasts sharply with the modern city pressing in from all sides. Since becoming a UNESCO World Heritage Site in 1987, the Palace Museum has undergone extensive restoration while managing crowds that now exceed 19 million visitors per year, making it the most visited museum in the world. Height restrictions on surrounding buildings preserve the sightlines that once ensured nothing in Beijing dared rise above the emperor's roof.