BBC documentary reveals secrets of Forbidden City

A scene from Secrets of China's Forbidden City. [Photo/Screen capture of Secrets of China's Forbidden City]

Untold architectural secrets of the Forbidden City, one of the greatest wonders of the medieval world, have come under the spotlight of BBC Channel 4 documentary, Secrets of China's Forbidden City.

The Forbidden City, the biggest wooden structure on Earth and a place of staggering wealth and power, was built under the order of Emperor Yongle of the Ming Dynasty (1368-1644).

The city is spread over 178 acres, 10 time that of France's Palace of Versailles. The city originally housed 900 buildings with 9,999 rooms, just one less than the divine number of 10,000, which was reserved for heaven.

How was such an engineering marvel was created in a time when only the most rudimentary tools were available, and how did it survive 600 years of war, upheavals and natural disasters?

Secrets of China's Forbidden City taps in to these questions from visits to its workshops and research labs, with particular focus on two aspects: transportation of materials and how it withstood natural disasters.

Shipping

Nanmu, the rarest of all Chinese woods, was widely used in the construction of the palace for its density and beauty. It is reported that some 10,000 nanmu logs were shipped from forests more than 18,000 km southwest of Beijing. Furthermore, golden floor tiles from 1,000 km south and 18 million bricks, each weighing 24 kg, also had to be transported to the capital, a task that seems unachievable in an unindustrialized world.

Ancient Chinese people had the wisdom to overcome that, through building the Grand Canal.

"The Grand Canal, which is both older and longer than the Panama Canal and the Suez Canal, solved a large problem of canal engineering at the time," said Jim Griffiths, a hydrologist.

The Grand Canal started from the commercial hub of Hangzhou to the south, passed tributaries of Yangtze and Yellow rivers and reached far north to Beijing. The nanmu logs were floated to Beijing along with a fleet of 20,000 barges with 200 million liters of grain to feed the one million workers each year.

But some materials were unsuitable to be shipped.

Emperor Yongle's grand staircase, a 16-meter-long hand-carved masterpiece that symbolizes his power, weighs more than 300 tons, equivalent to 125 Land Rovers.

The marble used in the staircase had to be transported from a quarry 60 km away, and obviously, no ship could withhold that much weight.