Radio Cadena Agramonte emisiora de Camagüey
The ruins of more than 130 secret passages in the Great Wall of China have recently been discovered by researchers from Tianjin University through a series of high-resolution photographs of the famous monument, reports Xinhua.
Each hidden door was designed to blend in with the local topography. In ancient times, these passages were used by reconnaissance groups, as well as merchants who transported goods inside and outside the wall.
Historical documents from the Ming dynasty (1368-1644) indicate that nomadic tribes were allowed to cross the grazing passes between Qinghai and Hetao in northwestern China, a region with abundant water and pasture resources at the time. Some doors were large enough for two horses to pass at the same time, explained team leader Zhang Yukun, a professor at Tianjin University.
Scientists claim that the discovery will allow a better understanding of the "complete and vivid architectural mechanism" of the Great Wall of China.
Likewise, the passages were camouflaged by the exterior with a thin brick wall, which the defenders of the wall could break from the inside at the right time to attack the enemy in a surprise.
The work of finding secret passages is complicated by the fact that it is very difficult to qualify the Great Wall as a single structure due to the history of its construction.
The first sections of the wall were built in the 3rd century B.C. during the so-called Warring Kingdoms period (475-221 a. C.). Moreover, these defensive structures were not erected around Chinese territory, but protected each of the four kingdoms fighting each other at the time.
Only under Qin Shi Huang, the first emperor of the first centralized Chinese state and founder of the Qin dynasty, did these protective walls unite into a common defense system.
The Qin Empire needed to protect itself from raids by nomads from the north, so the wall was expanded and strengthened.
As a result, the fortification system currently represents an irregular construction, an enormous defensive complex that is not arranged online. In some places, it consists only of towers that are not joined by a wall.
The total length of all sections of the Great Wall of China exceeds 21,000 kilometres. (RT) (Photo: www.globallookpress.com)
