Great Wall of China
|Great Wall of China|
The Great Wall of China at Jinshanling
Map of all the wall constructions
|Size||21,196 km (13,171 mi)1|
|Official name: The Great Wall|
|Criteria:||i, ii, iii, iv, vi|
|Designated:||1987 (11th session)|
|Great Wall of China|
|Literal meaning||long wall|
|Alternative Chinese name|
|Literal meaning||The long wall of 10,000 Li (里)2|
The Great Wall of China is a series of fortifications made of stone, brick, tamped earth, wood, and other materials, generally built along an east-to-west line across the historical northern borders of China in part to protect the Chinese Empire or its prototypical states against intrusions by various nomadic groups or military incursions by various warlike peoples or forces. Several walls were being built as early as the 7th century BC;3 these, later joined together and made bigger and stronger, are now collectively referred to as the Great Wall.4 Especially famous is the wall built between 220–206 BC by the first Emperor of China, Qin Shi Huang. Little of that wall remains. Since then, the Great Wall has on and off been rebuilt, maintained, and enhanced; the majority of the existing wall is from the Ming Dynasty.
Other purposes of the Great Wall have included border controls, allowing the imposition of duties on goods transported along the Silk Road, regulation or encouragement of trade and the control of immigration and emigration. Furthermore, the defensive characteristics of the Great Wall were enhanced by the construction of watch towers, troop barracks, garrison stations, signaling capabilities through the means of smoke or fire, and the fact that the path of the Great Wall also served as a transportation corridor.
The main Great Wall line stretches from Shanhaiguan in the east, to Lop Lake in the west, along an arc that roughly delineates the southern edge of Inner Mongolia. A comprehensive archaeological survey, using advanced technologies, has concluded that the Ming walls measure 8,850 km (5,500 mi).5 This is made up of 6,259 km (3,889 mi) sections of actual wall, 359 km (223 mi) of trenches and 2,232 km (1,387 mi) of natural defensive barriers such as hills and rivers.5 Another archaeological survey found that the entire wall with all of its branches measure out to be 21,196 km (13,171 mi).6
The collection of walls known today as the Great Wall of China was referred by a number of different names. The current English name evolved from enthusiastic accounts of "the Chinese wall" from early European travelers; by the end of the 19th century "the Great Wall of China" became the name of the walls.7 In Chinese, they are most commonly known as changcheng (長城), meaning "long wall". The term can be found in the Records of the Grand Historian (1st century BC), where it referred to the walls built by the Warring States, and most particularly, the walls of Qin Shi Huang.8 The notion of it being "ten thousand li" long (figuratively meaning "endless"), as reflected in the full Chinese name of the Great Wall in modern times (萬里長城 Wanli Changcheng), also comes from the Records, though the words "Wanli Changcheng" were rarely used together in pre-modern times—a rare example being the Book of Song written in 493, where it quotes the frontier general Tan Daoji.9
Historically, the dynasties after Qin avoided using the term changcheng to refer to their own "Great Walls", as the term was said to evoke imagery of Qin's tyranny.10 Instead, historical records indicate the use of various terms such as "frontier" (塞 sai),11 "rampart" (垣 yuan),11 "barrier" (障 zhang),11 "outer fortresses" (外堡 waibao),12 and "border wall" (邊牆 bianqiang),10 in addition to poetic and folk names like "purple frontier" (紫塞 zisai)13 and "earth dragon" (土龍 tulong).14 Only in modern times did changcheng become the catch-all term to refer to the long border walls regardless of location or dynastic origin, equivalent to the Western term "Great Wall".7
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.15 During this time and the subsequent Warring States period, the states of Qin, Wei, Zhao, Qi, Yan and Zhongshan1617 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 position the empire against the Xiongnu people from the north, he ordered the building of new walls to connect the remaining fortifications along the empire's 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. The human cost of the construction is unknown, but it has been estimated by some authors that hundreds of thousands,18 if not up to a million, workers died building the Qin wall.1920 Later, the Han,21 Sui, and the Northern dynasties all repaired, rebuilt, or expanded sections of the Great Wall at great cost to defend themselves against northern invaders.22 The Tang and Song Dynasties did not build any walls in the region substantially.22 The Liao, Jin, and Yuan dynasties, who ruled Northern China throughout most of the 10th–13th centuries, constructed defensive walls in the 12th century, but those were located much to the north of the Great Wall as we know it, within today's Inner and Outer Mongolia.23
The Great Wall concept was revived again during the Ming Dynasty in the 14th century,24 and following the Ming army's defeat by the Oirats in the Battle of Tumu. The Ming had failed to gain a clear upper hand over the 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 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.25 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.26 Qi Jiguang between 1567 and 1570 also repaired and reinforced the wall, faced sections of the ram-earth wall with bricks and constructed 1,200 watchtowers from Shanhaiguan Pass to Changping to warn of approaching Mongol raiders.27 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.28
Towards the end of the Ming Dynasty, 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 Shanhaiguan 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 rebels. Before this time, the Manchus had crossed the Great Wall multiple times to raid, but this time it was for conquest. The gates at Shanhaiguan were opened by the commanding Ming general Wu Sangui on May 25 who formed an alliance with the Manchus, hoping to use the Manchus to expel the rebels from Beijing.29 The Manchus quickly seized Beijing, and defeated both the rebel-founded Shun Dynasty and the remaining Ming resistance, establishing the Qing Dynasty rule over all of China.30
Under Qing rule, China's borders extended beyond the walls and Mongolia was annexed into the empire, so constructions on the Great Wall were discontinued. On the other hand, the so-called Willow Palisade, following a line similar to that of the Ming Liaodong Wall, was constructed by the Qing rulers in Manchuria. Its purpose, however, was not defense but rather migration control.
Foreign appreciation of the Wall
Arabs had heard about China's Great Wall as early as the 14th century. They associated it with Dhul-Qarnayn's Gog and Magog wall of the Qur'an, as the North African traveler Ibn Battuta heard from the local Muslim communities in Guangzhou around 1346.31
Soon after Europeans reached Ming China in the early 16th century, accounts of the Great Wall started to circulate in Europe, even though no European was to see it with his own eyes for another century. Possibly one of the earliest descriptions of the wall, and its significance for the defense of the country against the "Tartars" (i.e. Mongols), may be the one contained in the Third Década of João de Barros' Asia (published 1563).32 Other early accounts in Western sources include those of Gaspar da Cruz, Bento de Goes, Matteo Ricci, and Bishop Juan González de Mendoza.33 In 1559, in his work "A Treatise of China and the Adjoyning Regions," Gaspar da Cruz offers an early discussion of the Great Wall.33 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.34 Early European accounts were mostly modest and empirical, closely mirroring contemporary Chinese understanding of the Wall;35 although later they slid into hyperbole,36 including the erroneous but ubiquitous claim that the Ming Walls were the same ones that were built by Qin Shi Huang in the 3rd century BC.36
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,37 such that in the 20th century, a persistent misconception exists about the Great Wall of China being visible from the Moon or even Mars.38
Although a formal definition of what constitutes a "Great Wall" has not been agreed upon, making the full course of the Great Wall difficult to describe in its entirety,39 the course of the main Great Wall line following Ming constructions can be charted.
The Jiayu Pass, located in Gansu province, is the western terminus of the Ming Great Wall. Although Han fortifications such as Yumen Pass and the Yangguan exist further west, the extant walls leading to those passes are difficult to trace. From Jiayu Pass the wall travels discontinuously down the Gansu Corridor and into the deserts of Ningxia, where it enters the western edge of the Yellow River loop at Yinchuan. Here the first major walls erected during the Ming dynasty cuts through the Ordos Desert to the eastern edge of the Yellow River loop. There at Piantou Pass (偏頭關) in Xinzhou city, Shanxi province, the Great Wall splits in two with the "Outer Great Wall" (外長城) extending along the Inner Mongolia border with Shanxi into Hebei province, and the "inner Great Wall" (內長城) running southeast from Piantou Pass for some 400 kilometres (250 mi), passing through important passes like the Pingxing Pass and Yanmen Pass before joining the Outer Great Wall at Sihaiye (四海冶), in Yanqing County, Beijing.
The sections of the Great Wall around Beijing municipality are especially famous: they were frequently renovated and are regularly visited by tourists today. The Badaling Great Wall near Zhangjiakou is the most famous stretch of the Wall, for this was the first section to be opened to the public in the People's Republic of China, as well as the showpiece stretch for foreign dignitaries.40 South of Badaling is the Juyong Pass, when used by the Chinese to protect their land, this section of the wall had many guards to defend China’s capital Beijing. Made of stone and bricks from the hills, this portion of the Great Wall is 7.8 meters (26 ft) high and 5 meters (16 ft) wide.
One of the most striking sections of the Ming Great Wall is where it climbs extremely steep slopes. It runs 11 kilometers (6.8 mi) long, ranges from 5 to 8 meters (16 to 26 ft) in height, and 6 meters (20 ft) across the bottom, narrowing up to 5 meters (16 ft) across the top. Wangjinglou (望京樓) is one of Jinshanling's 67 watchtowers, 980 meters (3,220 ft) above sea level. Southeast of Jinshanling, is the Mutianyu Great Wall which winds along lofty, cragged mountains from the southeast to the northwest for approximately 2.25 kilometers (about 1.3 miles). It is connected with Juyongguan Pass to the west and Gubeikou to the east. This section was one of the first to be renovated following the turmoil of the Cultural Revolution.41
At the edge of the Bohai Gulf is the Shanhai Pass, the traditional end of the Great Wall known as the "Number One Pass Under Heaven" (天下第一關). The part of the wall that meets the sea is named the "Old Dragon Head" (老龍頭), within the Shanhai Pass complex. 3 km north of Shanhaiguan is Jiaoshan Great Wall (焦山長城), the site of the first mountain of the Great Wall.42 15 km northeast from Shanhaiguan, is Jiumenkou (九門口), which is the only portion of the wall that was built as a bridge.
Before the use of bricks, the Great Wall was mainly built from rammed earth, stones, and wood. During the Ming Dynasty, however, bricks were heavily used in many areas of the wall, as were materials such as tiles, lime, and stone. The size and weight of the bricks made them easier to work with than earth and stone, so construction quickened. Additionally, bricks could bear more weight and endure better than rammed earth. Stone can hold under its own weight better than brick, but is more difficult to use. Consequently, stones cut in rectangular shapes were used for the foundation, inner and outer brims, and gateways of the wall. Battlements line the uppermost portion of the vast majority of the wall, with defensive gaps a little over 30 cm (12 in) tall, and about 23 cm (9.1 in) wide. From the parapets, guards could survey the surrounding land.43 Communication between the army units along the length of the Great Wall, including the ability to call reinforcements and warn garrisons of enemy movements, was of high importance. Signal towers were built upon hill tops or other high points along the wall for their visibility. Wooden gates could be used as a trap against those going through. Barracks, stables, and armories were built near the wall's inner surface.43
While some portions north of Beijing and near tourist centers have been preserved and even extensively renovated, in many locations the Wall is in disrepair. Those parts might serve as a village playground or a source of stones to rebuild houses and roads.44 Sections of the Wall are also prone to graffiti and vandalism. Parts have been destroyed because the Wall is in the way of construction.45
More than 60 km (37 mi) 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 more than 5 metres (16 feet) to less than 2 metres (6.6 ft). The square lookout towers that characterize the most famous images of the wall have disappeared completely. Many western sections of the wall are constructed from mud, rather than brick and stone, and thus are more susceptible to erosion.46 In August 2012, a 30-meter (98 ft) section of the wall in north China's Hebei province collapsed after days of continuous heavy rains.47
Visibility from space
Visibility from the Moon
One of the earliest known references to this myth appears in a letter written in 1754 by the English antiquary William Stukeley. Stukeley wrote that, "This mighty wall of four score miles in length (Hadrian's Wall) is only exceeded by the Chinese Wall, which makes a considerable figure upon the terrestrial globe, and may be discerned at the Moon."48 The claim was also mentioned by Henry Norman in 1895 where he states "besides its age it enjoys the reputation of being the only work of human hands on the globe visible from the Moon."49 The issue of "canals" on Mars was prominent in the late 19th century and may have led to the belief that long, thin objects were visible from space.50 The claim that the Great Wall is visible also appears in 1932's Ripley's Believe It or Not! strip51 and in Richard Halliburton's 1938 book Second Book of Marvels.
The claim the Great Wall is visible has been debunked many times,52 but is still ingrained in popular culture.53 The wall is a maximum 9.1 m (30 ft) wide, and is about the same color as the soil surrounding it. Based on the optics of resolving power (distance versus the width of the iris: a few millimeters for the human eye, meters for large telescopes) only an object of reasonable contrast to its surroundings which is 70 mi (110 km) or more in diameter (1 arc-minute) would be visible to the unaided eye from the Moon, whose average distance from Earth is 384,393 km (238,851 mi). The apparent width of the Great Wall from the Moon is the same as that of a human hair viewed from 3.2 kilometres (2 mi) away. To see the wall from the Moon would require spatial resolution 17,000 times better than normal (20/20) vision.54 Unsurprisingly, no lunar astronaut has ever claimed to have seen the Great Wall from the Moon.
Visibility from low Earth orbit
A more controversial question is whether the Wall is visible from low Earth orbit (an altitude of as little as 160 kilometres (100 mi)). NASA claims that it is barely visible, and only under nearly perfect conditions; it is no more conspicuous than many other man-made objects.55 Other authors have argued that due to limitations of the optics of the eye and the spacing of photoreceptors on the retina, it is impossible to see the wall with the naked eye, even from low orbit, and would require visual acuity of 20/3 (7.7 times better than normal).54
Astronaut William Pogue thought he had seen it from Skylab but discovered he was actually looking at the Grand Canal of China near Beijing. He spotted the Great Wall with binoculars, but said that "it wasn't visible to the unaided eye." U.S. Senator Jake Garn claimed to be able to see the Great Wall with the naked eye from a space shuttle orbit in the early 1980s, but his claim has been disputed by several U.S. astronauts. Veteran U.S. astronaut Gene Cernan has stated: "At Earth orbit of 100 to 200 miles (160 to 320 km) high, the Great Wall of China is, indeed, visible to the naked eye." Ed Lu, Expedition 7 Science Officer aboard the International Space Station, adds that, "it's less visible than a lot of other objects. And you have to know where to look."
In 2001, Neil Armstrong stated about the view from Apollo 11: "I do not believe that, at least with my eyes, there would be any man-made object that I could see. I have not yet found somebody who has told me they've seen the Wall of China from Earth orbit. ...I've asked various people, particularly Shuttle guys, that have been many orbits around China in the daytime, and the ones I've talked to didn't see it."56
In October 2003, Chinese astronaut Yang Liwei stated that he had not been able to see the Great Wall of China. In response, the European Space Agency (ESA) issued a press release reporting that from an orbit between 160 and 320 kilometres (99 and 199 mi), the Great Wall is visible to the naked eye. In an attempt to further clarify things, the ESA published a picture of a part of the “Great Wall” photographed from low orbit. However, in a press release a week later (no longer available in the ESA’s website), they acknowledged that the "Great Wall" in the picture was actually a river.54
Leroy Chiao, a Chinese-American astronaut, took a photograph from the International Space Station that shows the wall. It was so indistinct that the photographer was not certain he had actually captured it. Based on the photograph, the China Daily later reported that the Great Wall can be seen from 'space' with the naked eye, under favorable viewing conditions, if one knows exactly where to look.57 However, the resolution of a camera can be much higher than the human visual system, and the optics much better, rendering photographic evidence irrelevant to the issue of whether it is visible to the naked eye.54
"The First Mound"—at Jiayuguan, the western terminus
Great Wall of China near Jinshanling
The Great Wall of China at Badaling
A portion of the Great Wall of China at Simatai, overlooking the gorge
Mutianyu Great Wall, China. This is atop the wall on a section that has not been restored
The Old Dragon Head, the eastern end of the Great Wall where it meets the sea in the vicinity of Shanhaiguan
Great Wall at Dandong
- "China’s Great Wall Found To Measure More Than 20,000 Kilometers". Bloomberg. June 5, 2012. Retrieved June 6, 2012.
- 10,000 li = 6,508 km (4,044 mi). In Chinese, 10,000 figuratively means "infinite", and the number should not be interpreted for its actual value, but rather as meaning the "infinitely long wall".
- The New York Times with introduction by Sam Tanenhaus (2011). The New York Times Guide to Essential Knowledge: A Desk Reference for the Curious Mind. St. Martin's Press of Macmillan Publishers. p. 1131. ISBN 978-0-312-64302-7. "Beginning as separate sections of fortification around the 7th century B.C. and unified during the Qin Dynasty in the 3rd century B.C., this wall, built of earth and rubble with a facing of brick or stone, runs from east to west across China for over 4,000 miles."
- "Great Wall of China". Encyclopædia Britannica. "Large parts of the fortification system date from the 7th through the 4th century BC. In the 3rd century BC Shihuangdi (Qin Shihuang), the first emperor of a united China (under the Qin dynasty), connected a number of existing defensive walls into a single system. Traditionally, the eastern terminus of the wall was considered to be Shanhai Pass (Shanhaiguan) in eastern Hebei province along the coast of the Bo Hai (Gulf of Chihli), and the wall’s length—without its branches and other secondary sections—was thought to extend for some 4,160 miles (6,690 km)."
- "Great Wall of China 'even longer'". BBC. April 20, 2009. Retrieved April 20, 2009.
- "Great Wall of China even longer than previously thought". Canadian Broadcasting Corporation. June 6, 2012. Retrieved June 6, 2012.
- Hessler 2007, p. 59.
- Waldron 1983, p. 650. The character 城 cheng now means "city", but at the time of the Records, the character meant "wall" as well, since a city and its city wall were considered one and the same. See Lovell 2006, p. 25
- Waldron 1990, p. 202. Tan Daoji's exact quote: "So you would destroy your Great Wall of Ten Thousand Li!" (乃復壞汝萬里之長城) Note the use of the particle 之 zhi that differentiates the quote from the modern name.
- Waldron 1983, p. 651.
- Lovell 2006, p. 15.
- Waldron 1990, p. 49.
- Waldron 1990, p. 21.
- Waldron 1988, p. 69.
- "歷代王朝修長城" (in zh-hant). Chiculture.net. Retrieved October 24, 2010.
- "古代长城——战争与和平的纽带" (in zh-hans). Newsmth.net. Retrieved October 24, 2010.
- "万里长城" (in zh-hans). Newsmth.net. Retrieved October 24, 2010.
- Slavicek, Mitchell & Matray 2005, p. 35.
- Evans 2006, p. 3.
- "Defense and Cost of The Great Wall – page 3". Paul and Bernice Noll's Window on the World. Retrieved July 26, 2011.
- Coonan, Clifford (February 27, 2012). "British researcher discovers piece of Great Wall 'marooned outside China'". The Irish Times. Retrieved February 28, 2012.
- Waldron 1983, p. 653.
- Waldron 1983, p. 654; Haw 2006, pp. 52-54.
- Karnow 2008, p. 192.
- Szabó, Dávid & Loczy 2010, p. 220.
- Evans 2006, p. 177.
- "Great Wall at Mutianyu". Great Wall of China.
- Edmonds 1985, pp. 38-40.
- Lovell 2006, p. 254.
- Elliott 2001, pp. 1–2.
- Haw 2006, pp. 52-54.
- João de Barros, Ásia de João de Barros. Dos feitos que os portugueses fizeram no descobrimento dos mares e terras do Oriente., 3-a Década. Book 2, Chapter VII. Lisbon, 1563. This chapter is reproduced on pp. 186—204 of the 5th volume of the 1777 edition of Asia.
- Waldron 1990, pp. 204-5.
- Yule 1866, p. 579. This section is the report of Góis' travel, as reported by Matteo Ricci in De Christiana expeditione apud Sinas (published 1615), annotated by Henry Yule).
- Waldron 1990, pp. 2–4.
- Waldron 1990, p. 206.
- Waldron 1990, p. 209.
- Waldron 1990, p. 214.
- Hessler 2007, p. 60.
- Rojas 2010, p. 140.
- Lindesay 2008, p. 212.
- "Jiaoshan Great Wall". TravelChinaGuide.com. Retrieved September 15, 2010. "Jiaoshan Great Wall is located about 3 km (1.9 mi) from Shanhaiguan ancient city. It is named after Jiaoshan Mountain, which is the highest peak to the north of Shanhaiguan Pass and also the first mountain the Great Wall climbs up after Shanhaiguan Pass. Therefore Jiaoshan Mountain is noted as "The first mountain of the Great Wall"."
- Turnbull 2007, p. 29.
- Ford, Peter (2006, November 30). New law to keep China's Wall looking great. Christian Science Monitor, Asia Pacific section. Retrieved March 17, 2007.
- Bruce G. Doar: The Great Wall of China: Tangible, Intangible and Destructible. China Heritage Newsletter, China Heritage Project, Australian National University
- "China's Wall becoming less and less Great". Reuters. August 29, 2007. Retrieved August 30, 2007.
- "Section of China's Great Wall collapses in heavy rains". ndtv.com. Press Trust of India. August 9, 2012. Retrieved 2014-10-18.
- The Family Memoirs of the Rev. William Stukeley (1887) Vol. 3, p. 142. (1754).
- Norman, Henry, The Peoples and Politics of the Far East, p. 215. (1895).
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- "The Great Wall of China, Ripley's Believe It or Not, 1932.
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"Can you see the Great Wall of China from the moon or outer space?", Answers.com. Accessed May 12, 2010.
Cecil Adams, "Is the Great wall of China the only manmade object byou can see from space?", The Straight Dope. Accessed May 12, 2010.
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"Is China's Great Wall Visible from Space?", Scientific American, February 21, 2008. "... the wall is only visible from low orbit under a specific set of weather and lighting conditions. And many other structures that are less spectacular from an earthly vantage point—desert roads, for example—appear more prominent from an orbital perspective."
- "Metro Tescos", The Times (London), April 26, 2010. Found at The Times website. Accessed May 12, 2010.
- López-Gil 2008, pp. 3-4.
- "NASA – Great Wall of China". Nasa.gov. Retrieved July 31, 2010.
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- Haw, Stephen G. (2006). Marco Polo's China: a Venetian in the realm of Khubilai Khan. Volume 3 of Routledge studies in the early history of Asia. Psychology Press. ISBN 0-415-34850-1.
- Hessler, Peter (2007). "Letter from China: Walking the Wall". The New Yorker (May 21, 2007): 58–67.
- Karnow, Mooney, Paul and Catherine (2008). National Geographic Traveler: Beijing. National Geographic Books. p. 192. ISBN 1-4262-0231-8.
- Lindesay, William (2008). The Great Wall Revisited: From the Jade Gate to Old Dragon's Head. Harvard University Press. ISBN 978-0-674-03149-4.
- López-Gil, Norberto (2008). "Is it Really Possible to See the Great Wall of China from Space with a Naked Eye?". Journal of Optometry 1 (1): 3–4. doi:10.3921/joptom.2008.3.
- Lovell, Julia (2006). The Great Wall : China against the world 1000 BC - 2000 AD. Sydney: Picador Pan Macmillan. ISBN 9780330422413.
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- Slavicek, Louise Chipley; Mitchell, George J.; Matray, James I. (2005). The Great Wall of China. Infobase Publishing. p. 35. ISBN 0-7910-8019-6.
- Szabó, József; Dávid, Lóránt; Loczy, Denes, eds. (2010). Anthropogenic Geomorphology: A Guide to Man-made Landforms. Springer. ISBN 978-9-048-13057-3.
- Turnbull, Stephen R (January 2007). The Great Wall of China 221 BC-AD 164. Osprey Publishing. ISBN 978-1-84603-004-8.
- Waldron, Arthur (1983). "The Problem of The Great Wall of China". Harvard Journal of Asiatic Studies (Harvard-Yenching Institute) 43 (2): 643–663. JSTOR 2719110.
- Waldron, Arthur (1988). "The Great Wall Myth: Its Origins and Role in Modern China". The Yale Journal of Criticism (Johns Hopkins University Press) 2 (1): 67–104.
- Waldron, Arthur (1990). The Great Wall of China : from history to myth. Cambridge England New York: Cambridge University Press. ISBN 9780521427074.
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- Man, John. (2008). The Great Wall. London: Bantam Press. 335 pages. ISBN 978-0-593-05574-8.
- Michaud, Roland and Sabrina (photographers), & Michel Jan, The Great Wall of China. Abbeville Press, 2001. ISBN 0-7892-0736-2
- Schafer, Edward H. (1985) The Golden Peaches of Samarkand. Berkeley: University of California Press. ISBN 978-0-520-05462-2.
- Yamashita, Michael; Lindesay, William (2007). The Great Wall — From Beginning to End. New York: Sterling. 160 pages. ISBN 978-1-4027-3160-0.
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|Textbooks from Wikibooks|
|Learning resources from Wikiversity|
- International Friends of the Great Wall – organization focused on conservation
- UNESCO World Heritage Centre profile
- Enthusiast/scholar website (Chinese)
- Great Wall of China on In Our Time at the BBC. (listen now)
- Photoset of lesser visited areas of the Great Wall