Great wall of China was an ancient gigantic defensive project. It is one of the largest construction projects ever completed.
Great Wall of China is one of the greatest wonders of the world. It winds its way westward over the vast territory of China from the bank of the Yalu River and ends at the foot of snow-covered Qilianshan and Tianshan mountains. It is seldom that we see such a gigantic project in China or elsewhere in the world. The Chinese call it the Wall of 10,000 li. Its size is better seen on a map or from an aerial photograph. According to astronauts who looked back from the moon, of all projects built by man, the Great Wall of China is the most conspicuous seen in space.
The construction of the Great Wall started during the Warring States Period on 7th century B.C, it had a history of more than 2,500 years. Many dukedoms built walls in Central China to protect themselfs and their northern territories. When Qin Shihuang, the first emperor in Chinese history, unified China and established the first centralised feudal state in China, he decided to have the walls linked up and extended.
There were about one million people, one-fifth of China's population at the time, were involved in the project which took more than ten years. Most of the walls we see today were rebuilt during the Ming Dynasty in the 16th century. It extends from Shanhaiguan Pass in the east to Jiayuguan Pass in the west. It is the only construction that the American astronauts could recognize with their naked eyes on their first flight to the Moon.
Those who succeeded in climbing the wall today are often regarded as "Real heroes", from this we should realize the difficulty in climbing the wall, and can imagine how difficult it is to build the Great Wall without modern machinery at that time.
In Beijing, the Great Wall is about 630 km long, 6 sections of the Great Wall have been opened to visitors. There are Badaling Section, Juyongguan Section, Simatai Section, Mutianyu Section, Jinshanling Section and Gubeikou Section.
History
The Chinese were already familiar with the techniques of wall-building by the time of the Spring and Autumn Period, which began around the 8th century BC.[5][6] During the Warring States Period from the 5th century BC to 221 BC, the states of Qin, Wei, Zhao, Qi, Yan and Zhongshan[7][8] all constructed extensive fortifications to defend their own borders. Built to withstand the attack of small arms such as swords and spears, these walls were made mostly by stamping earth and gravel between board frames.Qin Shi Huang conquered all opposing states and unified China in 221 BC, establishing the Qin Dynasty. Intending to impose centralized rule and prevent the resurgence of feudal lords, he ordered the destruction of the wall sections that divided his empire along the former state borders. To protect the empire against intrusions by the Xiongnu people from the north, he ordered the building of a new wall to connect the remaining fortifications along the empire's new northern frontier. Transporting the large quantity of materials required for construction was difficult, so builders always tried to use local resources. Stones from the mountains were used over mountain ranges, while rammed earth was used for construction in the plains. There are no surviving historical records indicating the exact length and course of the Qin Dynasty walls. Most of the ancient walls have eroded away over the centuries, and very few sections remain today. Later, the Han, Sui, Northern and Jin dynasties all repaired, rebuilt, or expanded sections of the Great Wall at great cost to defend themselves against northern invaders. It is estimated that over 1 million workers died building the wall.[9]
The Great Wall concept was revived again during the Ming Dynasty, following the Ming army's defeat by the Oirats in the Battle of Tumu in 1449. The Ming had failed to gain a clear upper-hand over the Manchurian and Mongolian tribes after successive battles, and the long-drawn conflict was taking a toll on the empire. The Ming adopted a new strategy to keep the nomadic tribes out by constructing walls along the northern border of China. Acknowledging the Mongol control established in the Ordos Desert, the wall followed the desert's southern edge instead of incorporating the bend of the Huang He.
Unlike the earlier Qin fortifications, the Ming construction was stronger and more elaborate due to the use of bricks and stone instead of rammed earth. As Mongol raids continued periodically over the years, the Ming devoted considerable resources to repair and reinforce the walls. Sections near the Ming capital of Beijing were especially strong.[citation needed]
During the 1440s–1460s, the Ming also built a so-called "Liaodong Wall". Similar in function to the Great Wall (whose extension, in a sense, it was), but more basic in construction, the Liaodong Wall enclosed the agricultural heartland of the Liaodong province, protecting it against potential incursions by Jurched-Mongol Oriyanghan from the northwest and the Jianzhou Jurchens from the north. While stones and tiles were used in some parts of the Liaodong Wall, most of it was in fact simply an earth dike with moats on both sides.[10]
Towards the end of the Ming Dynasty, the Great Wall helped defend the empire against the Manchu invasions that began around 1600. Under the military command of Yuan Chonghuan, the Ming army held off the Manchus at the heavily fortified Shanhaiguan pass, preventing the Manchus from entering the Chinese heartland. The Manchus were finally able to cross the Great Wall in 1644, when the gates at Shanhaiguan were opened by Wu Sangui, a Ming border general who disliked the activities of rulers of the Shun Dynasty. The Manchus quickly seized Beijing, and defeated the newly founded Shun Dynasty and remaining Ming resistance, to establish the Qing Dynasty.
