Early walls stretches from
Lintao to Liaodong. The Chinese were already familiar with the techniques of
wall-building by the time of the
Spring and Autumn period between the 8th and 5th centuries BC. During this time and the subsequent
Warring States period, the states of
Zheng,
Chu,
Qin,
Wei,
Zhao,
Qi,
Lu,
Han,
Yan,
Zhongshan and
Zhou 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 of stone or by stamping earth and gravel between board frames. is the longest of all walls, from Mamitu, near
Yumenguan, to Liaodong. The state of
Qin emerged victorious in 221 BC; its ruler, now the
First Emperor of a unified China, intended to centralize rule and prevent the resurgence of feudal lords; in doing so, he ordered the destruction of the sections of the walls that divided his empire among the former states. To position the empire against the
Xiongnu people from the north, however, he ordered the building of new walls to connect the remaining fortifications along the northern frontier. "Build and move on" was a central guiding principle in constructing the wall, implying that the Chinese were not erecting a permanently fixed border. Transporting the large quantity of materials required for construction was difficult, so builders always tried to use local resources; stone was used in montane areas, while
rammed earth was used while building in the plains. There are no surviving historical records indicating the exact length and course of the Qin walls, as most of the ancient walls have eroded away over the centuries, and very few sections remain today. Later, the
Han, the
Northern dynasties and the
Sui all repaired, rebuilt, or expanded sections of the Great Wall at great cost to defend themselves against northern invaders. The
Tang and
Song dynasties did not undertake any significant effort in the region. Dynasties founded by non-Han ethnic groups also built border walls: the
Xianbei-ruled
Northern Wei, the
Khitan-ruled
Liao,
Jurchen-led
Jin and the
Tangut-established
Western Xia, who ruled vast territories over Northern China throughout centuries, all constructed defensive walls, albeit being further north—reaching into the environs of present-day
Mongolia—than Han-built fortifications.
Ming and Qing eras The
Ming dynasty made substantial contributions to the Great Wall, following their defeat to the
Oirats in the
Battle of Tumu. This defeat had come in the context of protracted conflict with
Mongol tribes; a new strategy for defense was thus realized 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
Yellow River. Unlike the earlier fortifications, the Ming construction was stronger and more elaborate, due to the use of bricks and stone instead of rammed earth. Up to 25,000 watchtowers are estimated to have been constructed on the wall. 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. Under general
Qi Jiguang's supervision, 1,200 watchtowers from Shanhaiguan Pass to Changping were constructed between 1567 and 1570, and sections of the ram-earth wall were faced with bricks. During the mid–15th century, the Ming also built a so-called "Liaodong Wall". It enclosed the agricultural heartland of the
Liaodong province, protecting it against potential incursions by Jurchen-Mongol Oriyanghan from the northwest and the
Jianzhou Jurchens from the north. While stones and tiles were sometimes used here, it was otherwise simply an earth dike with moats on both sides. Towards the end of the Ming, the Great Wall helped defend the empire against the
Manchu invasions that began around 1600. Even after the loss of all of
Liaodong, the Ming army held the heavily fortified
Shanhai Pass, preventing the Manchus from conquering the Chinese heartland. The Manchus were finally able to cross the Great Wall in 1644, after Beijing had already fallen to
Li Zicheng's short-lived
Shun dynasty. Before this time, the Manchus had crossed the Great Wall multiple times to raid, but this time it was for conquest. The gates at Shanhai Pass were opened on May 25 by the commanding Ming general,
Wu Sangui, who formed an alliance with the Manchus, hoping to use the Manchus to expel the rebels from Beijing. The Manchus quickly seized Beijing instead, and eventually defeated both the Shun dynasty and the
remaining Ming resistance, consolidating the rule of the
Qing dynasty over all of
China proper. Under Qing rule and the
annexation of Mongolia into the empire, China's borders extended beyond the Great Wall; work on it for the purpose of border defense was thus discontinued. Construction nevertheless persisted with projects like the
Willow Palisade; following a line similar to that of the Liaodong Wall of the Ming, it was meant to prevent Han Chinese migration into Manchuria.
Foreign accounts None of the
Europeans who visited China or Mongolia in the 13th and 14th centuries, such as
Giovanni da Pian del Carpine,
William of Rubruck,
Marco Polo,
Odoric of Pordenone and
Giovanni de' Marignolli, mentioned the Great Wall. The North African traveler
Ibn Battuta, who also visited China during the
Yuan dynasty , had heard about China's Great Wall, possibly before he had arrived in China. He wrote that the wall is "sixty days' travel" from Zeitun (modern
Quanzhou) in his travelogue
Gift to Those Who Contemplate the Wonders of Cities and the Marvels of Travelling. He associated it with the
legend of the wall mentioned in the
Qur'an, which
Dhul-Qarnayn (commonly associated with
Alexander the Great) was said to have erected to protect people near the land of the rising sun from the savages of
Gog and Magog. However, Ibn Battuta could find no one who had either seen it or knew of anyone who had seen it, suggesting that although there were remnants of the wall at that time, they were not significant. Soon after Europeans reached Ming China by ship in the early 16th century, accounts of the Great Wall started to circulate in Europe, even though no European was to see it for another century. Possibly one of the earliest European descriptions of the wall and of its significance for the defense of the country against the "
Tartars" (i.e. Mongols) may be the one contained in
João de Barros's 1563
Asia. Other early accounts in Western sources include those of
Gaspar da Cruz,
Bento de Goes,
Matteo Ricci, and Bishop
Juan González de Mendoza, the latter in 1585 describing it as a "superbious and mightie work" of architecture, though he had not seen it. In 1559, in his work "A Treatise of China and the Adjoyning Regions", Gaspar da Cruz offers an early discussion of the Great Wall. Perhaps the first recorded instance of a European actually entering China via the Great Wall came in 1605, when the Portuguese Jesuit brother
Bento de Góis reached the northwestern
Jiayu Pass from India. Early European accounts were mostly modest and empirical, closely mirroring contemporary Chinese understanding of the Wall, although later they slid into hyperbole, including the erroneous but ubiquitous claim that the Ming walls were the same ones that were built by the first emperor in the 3rd century BC. When China opened its borders to foreign merchants and visitors after its defeat in the
First and
Second Opium Wars, the Great Wall became a main attraction for tourists. The
travelogues of the later 19th century further enhanced the reputation and the mythology of the Great Wall. ==Course==