Unexpected discovery of the Great Wall

The first detailed research project with modern technology shows that the length of the great citadel built over many dynasties in China is far greater than previous estimates.

A piece of the Great Wall is intact.Photo: China View.

The Chinese government's two-year research program for mapping the Great Wall of Great Wall discovered that this city wall stretches to 8,850 km. While familiar documents have long been written, the construction is about 5,000 km long and this estimate is often based on historical records.

Meanwhile, the new research project uses GPS global positioning technology and infrared technology, which helps locate some areas of the citadel buried over time by sandstorms. The project finds the walls of the city totaling 6,259 km and 359 km of trenches and 2,232 km of natural defensive roads such as hills and rivers.

The red line is the Great Wall under the Ming Dynasty (1368-1644).The broken lines are walls of previous dynasties (beginning in the 5th century BC).Graphic: BBC.

The research project is carried out by the National Authority for Cultural Heritage and the National Bureau of Map Survey. Experts said the newly discovered city walls were built during the Ming Dynasty (1368-1644). And the moat stretches from the Hu mountain range in northern Liaoning province to Jiayu pass in western Jiangsu province.

The study of the Great Wall will continue for another 18 months, to map the walls of the city built during the Qin Dynasty (221-206 BC BC) and the Han Dynasty (206 BC - 9 AD) Former SCN). This castle wall is the greatest man-made building in the world, built to protect the border with the north of Chinese dynasties.

Archaeologists have campaigned to implement this project, aiming to provide the world with an accurate understanding of the scale of the Great Wall. This work consists of various passages that began to be built in the 5th century BC and were first resumed during the Qin Shihuang period, around 220 BC.

In 1987, UNESCO recognized this as a world cultural heritage.