Title: Great Wall of China
Content:  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. The defensive lines contain multiple stretches of ramparts, trenches and ditches, as well as individual fortresses. In 2012, based on existing research and the results of a comprehensive mapping survey, the National Cultural Heritage Administration of China concluded that the remaining Great Wall associated sites include 10,051 wall sections, 1,764 ramparts or trenches, 29,510 individual buildings, and 2,211 fortifications or passes, with the walls and trenches spanning a total length of 21196 km. Incorporating advanced technologies, the study has concluded that the Ming Great Wall measure 8850 km. This consists of 6259 km of wall sections, 359 km of trenches and 2232 km of natural defensive barriers such as hills and rivers. In addition, Qin, Han and earlier Great Wall sites are 3080 km long in total; Jin dynasty (1115–1234) border fortifications are 4010 km in length; the remainder date back to Northern Wei, Northern Qi, Sui, Tang, the Five Dynasties, Song, Liao and Xixia. About half of the sites are located in Inner Mongolia (31%) and Hebei (19%).
Title: List of walls
Content: 🇨🇳 The Great Wall of China, China - part of UNESCO site 438,. This is mostly referred to the Ming Great Wall, built from 1368 to 1644, measures 8,850 km long. ; 🇨🇳 Great Wall of Qi, the oldest of the Chinese Great Walls. ; 🇮🇳 Kumbalgarh Fort wall Udaipur in Rajasthan, India's second largest fort ; 🇨🇳 Great Wall of Yan (state) ; 🇨🇳 Great Wall of Zhongshan (state) ; 🇨🇳 Great Wall of Zhao (state) ; 🇨🇳 Great Wall of Qin dynasty ; 🇨🇳 Great Wall of Han dynasty (206 BC–220 AD), the longest Great Wall in history. ; 🇨🇳 Great Wall of Northern Wei dynasty ; 🇨🇳 Great Wall of Northern Qi dynasty ; 🇨🇳 Great Wall of the Jurchen Jin Dynasty (1115-1234), 
Title: Ming Great Wall
Content:   The Ming Great Wall, built by the Ming dynasty (1368–1644), forms the most visible parts of the Great Wall of China today. A comprehensive archaeological survey, using advanced technologies, has concluded that the Ming walls measure 8850 km from Jiayu Pass in the west to the sea in Shanhai Pass, then looping over to terminate in Manchuria at the Hushan Great Wall. This is made up of 6259 km sections of actual wall, 359 km of trenches and 2232 km of natural defensive barriers such as hills and rivers. While the Ming walls are generally referred to as "Great Wall" (changcheng) in modern times, in Ming times they were called "border barriers" (邊牆; bianqiang) by the Chinese, since the term changcheng was said to evoke imagery of the tyranny of Qin Shi Huang (260–210 BC) and was associated with the Qin Great Wall.
Title: Great Wall of China
Content:  Wall" ( t , s , Nèi Chǎngchéng) running southeast from Piantou Pass for some 400 km, passing through important passes like the Pingxing Pass and Yanmen Pass before joining the Outer Great Wall at Sihaiye (, Sìhǎiyě), in Beijing's Yanqing County. 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. The Badaling Great Wall saw nearly 10 million visitors 
Title: Great Wall of China
Content:  control of immigration and emigration. Furthermore, the defensive characteristics of the Great Wall were enhanced by the construction of watchtowers, 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 frontier walls built by different dynasties have multiple courses. Collectively, they stretch from Liaodong in the east to Lop Lake in the west, from the present-day Sino–Russian border in the north to Tao River (Taohe) in the south; along an arc that roughly delineates the edge of the Mongolian steppe; spanning over 20000 km in total. Today, the defensive system of the Great Wall is generally recognized as one of the most impressive architectural feats in history.
Title: Great Wall of China
Content:  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 c. 1346, 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, 
Title: Great Wall of Qi
Content:   The Great Wall of Qi is the oldest existing Great Wall in China. Construction of the wall started in 441 BC (during the Spring and Autumn period) by the state of Qi, to defend itself against attacks from the states of Jin and Yue. Construction ended during the Warring States period and became Qi's defense against enemies states like Ju, Lu, and Chu. The wall stretches from the areas under the administration of the present-day city of Jinan to the present-day city of Qingdao across the territories of the present-day cities of Tai'an, Zibo, Laiwu, Weifang, Linyi, and Rizhao. Its total length has been estimated at about 600 kilometers. Most of the wall is still able to be seen.
Title: Ming Great Wall
Content:  a combined effort between Yu Zijun and Wang Yue, stretched from present day Hengcheng (橫城) in Lingwu (northwestern Ningxia province) to Huamachi town (花馬池鎮) in Yanchi County, and from there to Qingshuiying (清水營) in northeastern Shaanxi, a total of more than 2000 li (about 1100 km) long. Along its length were 800 strong points, sentry posts, beacon-fire towers, and assorted defences. 40,000 men were enlisted for this effort, which was completed in several months at a cost of over one million silver taels. This defence system proved its initial worth in 1482, when a large group of Mongol raiders were 
Title: Great Wall of China
Content:  The Great Wall of China is a series of fortifications that were built across the historical northern borders of ancient Chinese states and Imperial China as protection against various nomadic groups from the Eurasian Steppe. Several walls were built from as early as the 7th century BC, with selective stretches later joined together by Qin Shi Huang (220–206 BC), the first emperor of China. Little of the Qin wall remains. Later on, many successive dynasties built and maintained multiple stretches of border walls. The best-known sections of the wall were built by the Ming dynasty (1368–1644). Apart from defense, 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 
Title: Great Wall of China
Content:  t, s , Wàngjīng Lóu) is one of Jinshanling's 67 watchtowers, 980 m above sea level. Southeast of Jinshanling is the Mutianyu Great Wall which winds along lofty, cragged mountains from the southeast to the northwest for 2.25 km. 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. At the edge of the Bohai Gulf is Shanhai Pass, considered the traditional end of the Great Wall and the "First Pass Under Heaven". The part of the wall inside Shanhai Pass that meets the sea is named the "Old Dragon Head". 3 km 

Question: how many kilometers of great wall of china?
Answer: 8,850 km.
21,196 km.