Great Wall of China is an ancient Chinese fortification built and rebuilt between the 5th century AD. and the sixteenth century to protect the northern border of the Chinese empire during the successive dynasties of imperial attacks xiongnu nomads of Mongolia and Manchuria.
Not counting its ramifications and secondary buildings, covered 6400 km from the border with South Korea at the edge of the Yalu River to the Gobi Desert along an arc that roughly delineates the southern edge of Inner Mongolia, but today only one is kept 30% of it. The average is 6 to 7 meters and 4 to 5 meters wide. Ming in his heyday, he was guarded by more than a million warriors.
The wall was named a World Heritage Site by Unesco in 1987. Much of the Great Wall is reputed to be the largest cemetery in the world. Approximately 10 million workers who died during construction. They were not buried in the wall itself but in its immediate vicinity.
On 7/7/2007 the Wall of China was named as one of the winners on the list of the Seven Wonders of the Modern World.
In the eighth century AD, at the beginning of the period known as spring and fall, China is still a feudal system, the territory is divided into hundreds of fiefdoms run by princes or states, in theory, all gathered under the Zhou Dynasty kings. But over time, they were annexed by the feudal princes great principalities formed in the sixth century AD some were Chu and Wu, China was rapidly fragmented into several independent kingdoms: the beginning of the Realm Fighters.
By then, several states are committed to building walls to protect their neighbors and foreign peoples. Thus, about V century AD The state of Qi began building a wall, some parts are still standing. In the mid-fourth century AD.
The state of Wei began building a wall on its western border, close to Qi, and a second wall on its eastern border. She was followed by the states of Yan and Zhao.
Commonly, the technique used for the walls was layers of soil a few centimeters are packed one on top of another. Wooden boards were removed, leaving a wall of earth. This method could quickly develop solid walls that can withstand centuries.
In the year 221 AD, Qin Shi Huang conquered all opposing states and unified China is establishing the Qin Dynasty. Intended to impose a central government and prevent the resurgence of feudal lords, he ordered the destruction of the walls that divided his empire along the former border. After the attacks of the Xiongnu tribes in the north, sent General Meng Tian to ensure that the defeat of the Xiongnu, and then launch the construction of a wall beyond the Yellow River to better protect new territories conquered by connecting the remaining fortifications along the new northern border. The transport of a large amount of materials needed for construction was difficult, so the builders used local resources such as stones in the construction of rammed earth and the mountains to the construction in the plains.
There are no historical records indicating the exact length and layout of the wall in the Qin dynasty, but in spite of the debate among historians and the absence of historical events, the Great Wall built by the Qin dynasty remains in the popular imagination as a Chinese colossal work with the nickname “Wall of ten thousand li” (5,760 km in the value of li Qin Dynasty).
210 AD, Emperor Qin Shi Huang Qin Dynasty died and who survived founded a few years. In the 202 AD, Liu Bang, a former soldier of peasant origin who was a teacher in China and was proclaimed emperor under the name Han Gaozu. Weakened by their previous war of succession against General Xiang Yu, Gaozu leaves the maintenance of the Wall of Qin era, as the Xiongnu, now united in a confederation were threatening across the border, Gaozu, rather than adopting a offensive using the walls as well as Qin Shi Huang, is trying to achieve peace with honors and a “harmonious union” or heqin, ie the supply of Chinese princesses for the heads Xiongnu. For several decades, his successors will do the same. However, the Great Wall is not completely abandoned: under the rule of Emperor Han Wudi it recommends the establishment of borders tuntian (types of military-agricultural settlements) protected by small walls to colonize the region and prevent the Xiongnu raids.
In 134 AD the status quo between the Chinese and the Xiongnu was broken, unlike his ancestors, wudi have decided to take an offensive against the Xiongnu confederation and started in 129 a. C. a first offense, followed by many others. Wudi connected and restored portions of the Wall of the Qin Dynasty and then spread across what became the Silk Road. 119 a. C., the Xiongnu are expelled through the Gobi desert in Inner Mongolia, and a new section of wall, 400 km long was built and is kept current.
In year 9 BC., the Han dynasty is overshadowed by the short-lived Xin Dynasty, before being restored to 23 BC. by Emperor Shi di Geng faced a civil war and when the Emperor Guang Wudi ascended the throne two years later, his army is too weak to effectively contain the Xiongnu. He ordered the construction of four new walls to halt their advance and protect the capital.
Finally, about 48, the Xiongnu experienced infighting and divided into two groups: Xiongnu Northern Xiongnu and the South. Serve the southern Xiongnu buffer between their counterparts in northern China and was willing to coexist with them. At the end of the Han dynasty, China was divided into three kingdoms, separated by borders, making the construction and maintenance of large walls irrelevant.
While some parts north of Beijing and near tourist centers have been preserved and even reconstructed, in many places the wall is in poor condition. The parties have served as a source of stones to rebuild houses and roads. The sections of the Wall are also prone to graffiti and vandalism. Has been destroyed, because it is in the way of construction. No comprehensive survey of the wall has been carried out, so it is not possible to say how much of it survives, especially in remote areas.
Over 60 kilometers of the wall in Gansu province may disappear in the next 20 years due to erosion from sandstorms. In places, the height of the wall has been reduced from over five meters to less than two meters. The lookout towers that characterize the most famous images of the wall have disappeared completely. Many western sections of wall were built from mud, rather than brick and stone, and are therefore more susceptible to erosion.