Historical meteorology of Huan county

The Great Wall of Wan Li, represented by the Great Wall of Qin and Han Dynasties and the Great Wall of Ming Dynasty, starts from Yumenguan, Gansu Province, along the north side of Hexi Corridor, along the junction of desert and loess plateau to the east, and then along the interlaced zone between Inner Mongolia Plateau and northern mountainous areas of Hebei Province, meanders on the backs of Yanshan Mountain and Taihang Mountain, and reaches the edge of the sea along the mountain trend. Its southeast is dominated by plains and hills. Except the Loess Plateau, most of them are plains below 200 meters above sea level and hills below 500 meters above sea level. The terrain is flat and open, and the cultivated land is concentrated. There are Alashan Plateau, Inner Mongolia Plateau and Daxinganling Mountains in the north from west to east, and most of them are above 1000 meters above sea level, which is the largest and most concentrated area of natural grassland in China.

Most of the areas where the Great Wall is located are hills that transition from plateau to plain. Low mountain area. The layout of the Great Wall was chosen in this transitional terrain, on the one hand, because the mountains that were not very steep were always valued in ancient wars. When the productivity level is low and the infantry and cavalry are fighting on their own, natural disasters such as rivers and mountains can be used as an important part of the defense system without the need to build military facilities.

Moreover, it was difficult to build a large-scale city wall on a steep mountain with the means of transportation, material sources and technical level at that time. Therefore, the layout of the early ancient war defense system mainly used natural facilities.

Only a few sections of the Great Wall of each generation are really built on high mountains. The Great Wall in the Warring States Period, the Great Wall in the Qin and Han Dynasties, the Great Wall in the Jin Dynasty and the Great Wall in the Ming Dynasty almost all made use of the transition surface from the plateau to the plain, which is dominated by low mountains and hills. On the other hand, the terrain transition zone is often characterized by the fact that the absolute height of the terrain is not necessarily high, but the relative height difference is large, and the terrain is rugged and changeable, which is an excellent position for both offensive and defensive. Especially in the middle and eastern sections of the Great Wall Belt in the north.

The middle part includes Ningxia, Inner Mongolia, Shaanxi, western Shanxi and other provinces. Due to the strong crustal movement during the geological period, a series of border mountains such as Helan Mountain, Langshan Mountain and Daqingshan Mountain were formed between the Mongolian Plateau and the Loess Plateau. The mountains are asymmetrical, gentle in the north and steep in the south. The eastern part of the Great Wall Belt, including the present northern Shanxi, Hebei, Liaoning and eastern Inner Mongolia, is in the transition zone from the Inner Mongolia Plateau to the Northeast and North China Plain. The main mountain ranges are Yanshan Mountain, Taihang Mountain, Daxing 'anling Mountain, Changbai Mountain, Liaodong Mountain and Western Liaoning Hill.

Because of the crustal movement, the mountainous area has been uplifted many times, and the two terraces are relatively high and the terrain is steep. The Inner Mongolia Plateau in the north of the Great Wall Belt is flat, with no mountains, only rolling hills and mounds. South of the Great Wall is the endless North China Plain. Indeed, the desert in the north is vast and the land in the south is fertile. The rugged transition zone in the middle is of course the best military base for ambush, observation and throat control.

Water condition is a very sensitive environmental factor in this region, which directly affects the survival of regional people and animals and the development of regional economy. Except that the eastern and western ends of the Great Wall are located in semi-humid and arid areas respectively, most of the sections are located in semi-arid climate areas where the semi-humid climate changes to arid climate areas in China, which forms the staggered distribution of agriculture and animal husbandry in the agricultural production of the Great Wall, leading to frequent fluctuations in the boundary space of agriculture and animal husbandry.

The dividing line between agricultural areas and pastoral areas

The Great Wall is the dividing line between China's important agricultural areas and pastoral areas.

The position of the Great Wall in ancient Qin and Han Dynasties is roughly the same as the dividing line between agriculture and animal husbandry in northern China today. South of the line is an agricultural area dominated by farming in China; To the north of the line is the grassland area in northern China. From the Warring States to the Qin and Han Dynasties, the position of the Great Wall moved north and west with the expansion of agricultural areas to the north and west. During the Warring States Period, the agricultural area of China was limited to the Central Plains with the Yellow River as the center. There are Taiyuan and Zhongshan in the north, the sea in the east and Xining in the west. Its northern part includes Tianshui, Anding, Beidi, Shang Jun and Hexi Corridor, all of which belong to animal husbandry economic zone.

At that time, the Loess Plateau was still a forest grassland. In order to prevent the northern nomads from invading the central region, Qin, Zhao and Yan Dou built the Great Wall on the edge of the agricultural area at that time. During the Warring States Period, Qin Changcheng built the Great Wall to defend the Guanzhong Plain centered on Xianyang. It runs from Lintao, Gansu to the east, passes through Guyuan, Ningxia, reaches Huanxian in the north, Yulin in northern Shaanxi, then turns to the northeast and ends on the west bank of the Yellow River.

This section of the Great Wall was generally the western section of the dividing line between agriculture and animal husbandry at that time; The Great Wall in northern Zhao is an agricultural area centered on the capital Handan. The North Great Wall was built from Xuanhua, Hebei Province to the southwest along Sanggan River, to Hengshan Yanshan Mountain, and then to Yinshan Mountain in the northwest, ending in Gaoque. The Great Wall of Yanbei is an agricultural area centered on the thistle of Guodu, which is distributed in Zhangjiakou-Chifeng-Liaohe-Dandong today. The Great Wall of Yanzhao was roughly the same as the middle and eastern part of the dividing line between agriculture and animal husbandry at that time. After Qin Shihuang unified China, the former Yan, Zhao and Qin Changcheng were consolidated and repaired in the north and east.

At the same time, with the large-scale reclamation, the agricultural area expanded to the western Hetao area, and a section of the Great Wall was built from the Hetao area of Inner Mongolia to Lanzhou, Gansu Province through the foothills of Helan Mountain in Ningxia. Later, the expansion of the Great Wall in the Western Han Dynasty was also focused on the west. The Great Wall in Hexi Corridor was built to defend the newly expanded fertile Qingzhou planting industry, such as Jiuquan, Zhangye and Wuwei, and also to defend the Silk Road, the main traffic artery to the west.

So far, this section of the Great Wall is roughly consistent with the current dividing line between agriculture and animal husbandry. The Great Wall of the Ming Dynasty was mainly built to defend the Mongols in the north. Due to the change of the strength contrast between the two sides, the position of the Great Wall in Ming Dynasty was somewhat withdrawn from the Great Wall in Qin and Han Dynasties, which was roughly consistent with the boundary between agriculture and animal husbandry at that time. In this way, the Great Wall of Wan Li was originally a man-made city, but objectively it became the dividing line of agriculture and animal husbandry production, which reflected the division of agricultural cultural landscape and animal husbandry cultural landscape at that time and became an important archaeological evidence to restore the dividing line of agriculture and animal husbandry in this area.

View all 7 answers.

How to get to the Badaling Great Wall in Beijing _ Read it in one minute _ Let you spend less money _ How to get to the Badaling Great Wall in Beijing

How to get to the Badaling Great Wall in Beijing in one minute, how to get to the real Badaling Great Wall in Beijing in detail, cost-effective travel itinerary, how to get to the Badaling Great Wall in Beijing, worry-free, money-saving experience sharing, super classic travel route, including matters needing attention.

Zhangjiajie Longteng Tianxia International. Advertising?

Great Wall Quotes and Pictures-Feng Jun Series "Jun" presents a good gift, and buying a car is a triple gift!

Recommended information about the Great Wall worth seeing.

From now until 6.30, you can enjoy 3000 to 6000 1 year, 0 interest, and 3000/ vehicle replacement subsidy when you buy all models of Great Wall Feng Jun. Great Wall pickup truck has been selling well for 22 years in a row, with reliable quality and affordable price, which is worth buying!

Advertising for Great Wall Motor Co., Ltd.?

All related issues

The background (including geographical location), historical position, architectural style and characteristics of the Wan Li Great Wall are urgent! The more detailed, the better.

The Great Wall is the general name of large-scale military projects built in China in different periods in ancient times to resist the invasion of nomadic tribes in Saibei. The Great Wall was built in the Spring and Autumn Period and the Warring States Period in the 5th century BC. In the third century BC, Qin Shihuang unified China, sent Meng Tian to lead 300,000 troops to drive the Xiongnu north, and then connected the original sections of the Great Wall to continue construction. Since then, it has been continuously maintained and expanded, and/kloc-0 was built for more than 2,000 years around the middle of the 7th century. The Great Wall starts from Jiayuguan in Gansu in the west and ends at Yalu River in the east. It passes through 10 provinces, autonomous regions and municipalities from east to west. The Great Wall is the crystallization of the wisdom of the ancient people in China and a symbol of the Chinese nation. The structural content of the wall depends on the local climate conditions. Generally speaking, the construction methods of Wan Li Great Wall are as follows: 1. Rammed earth wall; 2. Adobe masonry wall 3. Brick wall 4. Stone wall 5. Brick masonry 6. Strip stone 7. Clay connecting brick. Bricks, stones and masonry are used to build city walls. When the slope of the terrain is small, bricklaying or masonry is parallel to the terrain, and when the local potential slope is large, the wall is built by horizontal descent method. 1382 snack food ranking, snack bar joining, national snack food discount pioneer! People who pay attention to joining snack shops are also watching the snack joining snack list! Snacks have joined more than 1000 stores across the country, and small stores have made a lot of money. All the historical position, architectural style and characteristics of the Great Wall in Wan Li and its military significance are related to Mobile.lsdsite.com's advertisements. The Great Wall is not only the front line of defense for farming people, but also the frontier base for launching counterattacks against nomadic people. The rear of the Great Wall is equipped with mobile troops to deal with the war, but the Great Wall is not the forefront of defense, and the observation post deployed in front of the Great Wall goes far. The ancient nomadic cavalry had excellent mobility and strong attack power, but they could do nothing about the wall defense system, so building the Great Wall could effectively resist the invasion of northern nationalities. Artistic value: The Great Wall is the pride and symbol of the Chinese nation, which embodies the sweat and wisdom of our ancestors. It is famous for its long history, huge project and magnificent spirit. People who have been to the Great Wall at all times and all over the world are amazed at its majestic momentum, grand scale and arduous project. The Great Wall is a rare treasure and a cultural relic with extraordinary art. It symbolizes the indestructible will and strength of the Chinese nation, the pride of the Chinese nation and the pride of all mankind. Great Wall Architectural Art Through research, we found that the Great Wall is a great project with rich architectural art characteristics. We studied the architectural art of the Great Wall from the following three aspects. (1) Great Wall 1 Structure and drainage system. Structure of the Great Wall in different sections: (1) Plain and hilly sections, such as Badaling Great Wall section, the walls are made of sand and blue bricks, which can bear large loads. These blue bricks are easy to make. Cheap and strong, it is the first choice for the Great Wall in plain and hilly areas. (2) In arid and semi-arid areas, such as Jiayuguan Great Wall, the wall is made of clay, coated layer by layer, and finally coated with a layer of loess as a protective layer. Adobe walls are most suitable for arid and semi-arid areas because they are suitable for areas with little rain and dry weather. ③ In mountainous areas, such as Simatai Great Wall, the walls are filled with gravel. It is made of strips of stone. Rocks can be found everywhere on high mountains. It is simple and practical to carve stones into strips to build the Great Wall. To sum up, we can see that although the Great Wall stretches across Wan Li, its wall structure is not uniform. The structure and materials of the Great Wall are changeable in form. It is not difficult to see that our ancestors considered the artistry of the Great Wall on the basis of practicality. 2. Drainage system of the Great Wall: The drainage system of the Great Wall is generally divided into two parts: drainage ditch and earthen spout. The drainage ditch is built on both sides of the wall walkway and is a long and narrow concave land. When it rains, the rainwater flows into the concave ground along the square brick and then is discharged from the wall through the spout. The spout was carved into the shape of an animal's head by a stonemason, which once again shows that the ancients not only considered the practicality of the Great Wall. We also attach great importance to its architectural artistry. Any building, if repeated blindly, will have no artistic value at all. (2) The scale is huge and stretches across Wan Li, giving people a great visual impact. There are also Great Walls abroad, some large and some small. For example, the Hadrian Great Wall in Britain is only a few hundred percent of the Great Wall in China, and its visual impact cannot be compared with the Great Wall in China. Secondly, it is about 4.5 meters high and 2.5-3 meters wide. It consists of about 750,000 cubic meters of stones. It was hastily built in the valley by the Roman king with his army, while the Great Wall in China was built by millions of migrant workers in decades. As a defense project, the Great Wall of China has climbed mountains and crossed deserts, grasslands, cliffs and rivers. The terrain it passes through is complex and the structure it uses is very strange. It can be described as a miracle in the history of ancient architectural engineering. Therefore, the Great Wall of China is unmatched by other Great Walls in scale. (3) The Great Wall bears rich cultural connotations. The Great Wall not only has distinctive architectural artistic features, but also has rich cultural connotations. The Great Wall of Wan Li has stood on the land of China for thousands of years. From the Great Wall now, we can see many historical vicissitudes and ancient cultural values. Among them, there are many touching stories about the Great Wall. It can be said that the Great Wall is the witness of China's history and the crystallization of the wisdom of the ancient working people in China. Many times, art carries rich cultural connotations and gives people a lot of imagination. At this time, people see not only the cold wall, but also the history. More vicissitudes. To sum up, the Great Wall of China is incomparable to other Great Walls in the world in appearance, structure, scale and use. The Great Wall bears rich cultural connotations and shows the characteristics of ancient architectural art in China. Browse 398920 18-05-03 Brief Introduction of Wan Li Great Wall 2 Browse 575902020-04-25 Main aesthetic features of the Great Wall architectural art in the traditional universe of China. This China's traditional view of the world is reflected in China's traditional aesthetics as superior beauty and magnificent beauty. In short, female beauty is the so-called "apricot blossom and spring rain in the south of the Yangtze River"; The beauty of masculinity is the so-called "steed, autumn wind, northern Hebei". The beauty of the Great Wall belongs to masculine beauty, that is, majestic. Magnificence is characterized by majestic, vigorous, grand and rough, and wins with momentum. Elegance is characterized by softness, charm, beauty, elegance, quietness and harmony, and it is known for its interest. The Great Wall, beautiful poems, poems by Han Yuwen and Su Xin, as well as Weibei in calligraphy, Qin figurines in sculpture, Buddha statues in Yungang, Longmen and Leshan, and the Forbidden City in architecture. , reflecting a kind of "harmony between man and nature" momentum and strong artistic appeal. If the feeling process of female beauty has the characteristics of "moistening things silently", then the works of masculine beauty will shock people in an instant. Judging from the functions of these two forms of beauty, it can be said that female beauty is of great significance to improve an independent and complete personality by focusing on the inner world and the cultivation of spiritual feelings that affect individual personality. The beauty of masculinity is of inestimable value and significance for inspiring a nation's self-confidence and spirit and thus promoting historical progress. "Since ancient times, no one has died in life, leaving Dan's heart to shine." Wen Tianxiang's famous words inspired countless people with lofty ideals to die for their country. Tragic and hard. The masculine beauty represented by the Great Wall has this profound connotation that affects historical creativity. Browse the information of 3303 Wan Li Great Wall, hurry up, do you want it? Urgent! The more detailed, the better! Since the collapse of Organ City, Mohist resistance has been almost completely eliminated. The Qin Empire returned to the dream of peace and prosperity ... In The Great Wall of Wan Li, the bright moon in Qin Dynasty, Ying Zheng of Xianyang Palace used countless laborers to build the Great Wall of Wan Li, and at the same time carried out some more sophisticated plans. Now this plan is almost completed, and the "Phantom" of the great ship assisted by the Yin and Yang family has been built. Its majestic and exquisite posture emerges beyond the sea level, just like the sea fairy mountain in everyone's dream. In order to solve the mystery of the "mirage", various factions and forces slowly gathered in this quiet seaside town. At this time, Tian Ming and Yu Shao, the protagonists of the story, are studying and living in the Scholars Manor in order to avoid Qin Jun's pursuit. Then all kinds of strange things happened here, and the calm of the town was completely broken. All life-and-death hatred and family hatred will unite at that moment. All eyes will gather in that place! All sentient beings are just pieces of city bricks, which are used to cast the Great Wall of Wan Li. 20 11/The first version of the trailer was released on 2011May1The second version was released on 2011September 29th, and has been sold in official website. For the link, please see the extended reading below. 2065438+0265438+1October 18, the first version of the sample (episode II: tight encirclement) was released, and the sample can be watched in Tudou and official website. February, 2065438+02 14 released the second edition of the demo (Episode 13: Shang Tong Rubik's Cube). In the finale of Bright Moon in the Sky in Qin Dynasty, Duanmu Rong is uncertain for Nie Gai. The third part is "My understanding of the Book of Changes is not enough to cure the injury of Duanmu." "I'll be back in ten days." It has been officially admitted that Duanmu Rong will not wake up in the fourth film. But officials said, "There will definitely be surprises next season." The awakening of Duanmu Rong is still the biggest wish of Rong fans. Mysterious Girl In the last few minutes of the finale of "Bright Moon in Qin Dynasty, Night at Dawn", the mysterious girl solemnly looked back. The fourth and second edition of the national day notice, she smiled. It is now confirmed that she is Shi Lan. In Shao Siming's second edition of the Fourth National Day notice, Shao Siming's lens accounted for a part of the proportion. Shao Siming stood on the eaves, as if looking at the white peak on the Bai Niao. Her short and wonderful fight with the thief showed her amazing strength. Some people think that Shao Siming, Xing Soul and Priestess of Death jointly besieged Yu Shao. Trailers for Nie Gai and Duanmu Rong show that Nie Gai collects medicinal materials for Duanmu Rong and silently looks at Duanmu Rong in the distance. Nie Rong has been officially matched. In the fourth issue of the second edition of Crimson Lotus National Day notice, many people found that Crimson Lotus had a new image-Korean princess. Such a warm pink silk dress, pink boots and a few tears will reveal Crimson Lotus's unknown past and her previous engagement. The fates of Crimson Lotus and Wei Zhao are also intertwined, which will be a new perspective. It is officially confirmed that Crimson Lotus was once a Korean princess-Honglian. 4 Browse 459 Wan Li Great Wall Profile/KOOC-0/25 Browse/KOOC-0//KOOC-0/04/KOOC-0/620/KOOC-0/9-/KOOC-0/-/KOOC-0/3 Wonderful recommendation Tom Cat Parkour _ mobile game download. Tom Cat Parkour game download, 4399 game box provides one-click download and installation of Tom Cat Hero Parkour mobile game, and use 4399 game box to find mobile games! 4399 network sharing has .. advertising Tom Cat Parkour _ mobile game download -TapTap found a good game? It is very convenient to download Tom Cat Hero Parkour mobile game in TapTap, and you can enjoy the pure game experience. Discover more good games in the TapTap community and share them with players around the world. Let's find a good game together. Easy to play (Shanghai) network technology .. What is the main reason for Zhuge Liang's failure in the Northern Expedition? During the first Northern Expedition, when Zhao Yun was still there, Zhuge Liang had many civil servants and military commanders, and Meng Huo in the south surrendered to the court. Zhuge Liang had no internal worries, so Zhao Yun and Deng Zhi debated 136. If the atom is the universe, can it come back after starting from the planet? 100 million is a big number, and once it is multiplied by 100 million times, it immediately becomes astronomical. Flower growers have thought more than once that if the whole country pays a dollar, Lao Tzu will be rich! In my opinion, this atom is really small. If magnified 100 million times, will there be a brand-new universe? 3673 Browse 37 Like a woman who hasn't had sex for a long time, what will happen in the end? People's Medicine Why is a girl beautiful, friendly and kind, but single for a long time? That's because you are so beautiful that other boys think you can't reach it, giving the average boy the feeling that all beautiful girls have boyfriends. So, do you really drift 18000 to browse 644 and answer why Yu-Ching Fei chose to quit the entertainment circle? The most important reason why Yu-Ching Fei quit the entertainment circle is that his parents' death gave him a great blow and made him lose the meaning of struggle. He wants to calm down and answer that Jupiter and the moon are protecting the earth. Is the solar system designed? In a sense, the massive planets in the solar system are protective. For example, Jupiter mentioned in this question is outside the orbit of Mars. Therefore, when many space debris move to the nearest planet, they pass through Jupiter's huge celestial bodies, and most of them will directly hit Jupiter under the action of gravity. Why has Sunny, who is very good at acting, never caught fire? Whether an actor can get angry or not requires not only his own strong ability, but also a suitable opportunity. For example, because "ipartment 4827 Browsing 3 1" answered why the rich have always been rich and the poor have always been poor? Check all 5 answers of kitchen and bathroom appliances, and the explosion will go straight down! ? JD.COM Shopping Center? All questions related to advertising will be answered by Guo Jin, Shanghai: There are many manufacturers of geological pipes, and Shanghai Guo Jin can be chosen as the geological pipe. The main products of Shanghai Guo Jin are casing, drill pipe, geological pipe, drilling rig, seamless pipe, mud pump, trenchless pipe jacking, diamond compact bit, etc ... Shanghai Guo Jin Metal Material Co., Ltd. implements direct supply mode and provides systematic services integrating wholesale, retail, processing, logistics and after-sales, which is mutually beneficial. The products are of good quality, complete variety and excellent price. 102018-09-10 The historical position, architectural style and characteristics of the Great Wall of Wan Li and its military significance. The Great Wall is not only the defensive front of the farming people, but also the forward base for launching a counterattack against the nomadic people. The rear of the Great Wall is equipped with mobile troops to deal with the war, but the Great Wall is not the forefront of defense, and the observation post deployed in front of the Great Wall goes far. The ancient nomadic cavalry had excellent mobility and strong attack power, but they could do nothing about the wall defense system, so building the Great Wall could effectively resist the invasion of northern nationalities. Artistic value: The Great Wall is the pride and symbol of the Chinese nation, which embodies the sweat and wisdom of our ancestors. It is famous for its long history, huge project and magnificent spirit. People who have been to the Great Wall at all times and all over the world are amazed at its majestic momentum, grand scale and arduous project. The Great Wall is a rare treasure and a cultural relic with extraordinary art. It symbolizes the indestructible will and strength of the Chinese nation, the pride of the Chinese nation and the pride of all mankind. Great Wall Architectural Art Through research, we found that the Great Wall is a great project with rich architectural art characteristics. We studied the architectural art of the Great Wall from the following three aspects. (1) Great Wall 1 Structure and drainage system. Structure of the Great Wall in different sections: (1) Plain and hilly sections, such as Badaling Great Wall section, the walls are made of sand and blue bricks, which can bear large loads. These blue bricks are easy to make. Cheap and strong, it is the first choice for the Great Wall in plain and hilly areas. (2) In arid and semi-arid areas, such as Jiayuguan Great Wall, the wall is made of clay, coated layer by layer, and finally coated with a layer of loess as a protective layer. Adobe walls are most suitable for arid and semi-arid areas because they are suitable for areas with little rain and dry weather. ③ In mountainous areas, such as Simatai Great Wall, the walls are filled with gravel. It is made of strips of stone. Rocks can be found everywhere on high mountains. It is simple and practical to carve stones into strips to build the Great Wall. To sum up, we can see that although the Great Wall stretches across Wan Li, its wall structure is not uniform. The structure and materials of the Great Wall are changeable in form. It is not difficult to see that our ancestors considered the artistry of the Great Wall on the basis of practicality. 2. Drainage system of the Great Wall: The drainage system of the Great Wall is generally divided into two parts: drainage ditch and earthen spout. The drainage ditch is built on both sides of the wall walkway and is a long and narrow concave land. When it rains, the rainwater flows into the concave ground along the square brick and then is discharged from the wall through the spout. The spout was carved into the shape of an animal's head by a stonemason, which once again shows that the ancients not only considered the practicality of the Great Wall. We also attach great importance to its architectural artistry. Any building, if repeated blindly, will have no artistic value at all. (2) The scale is huge and stretches across Wan Li, giving people a great visual impact. There are also Great Walls abroad, some large and some small. For example, the Hadrian Great Wall in Britain is only a few hundred percent of the Great Wall in China, and its visual impact cannot be compared with the Great Wall in China. Secondly, it is about 4.5 meters high and 2.5-3 meters wide. It consists of about 750,000 cubic meters of stones. It was hastily built in the valley by the Roman king with his army, while the Great Wall in China was built by millions of migrant workers in decades. As a defense project, the Great Wall of China has climbed mountains and crossed deserts, grasslands, cliffs and rivers. The terrain it passes through is complex and the structure it uses is very strange. It can be described as a miracle in the history of ancient architectural engineering. Therefore, the Great Wall of China is unmatched by other Great Walls in scale. (3) The Great Wall bears rich cultural connotations. The Great Wall not only has distinctive architectural artistic features, but also has rich cultural connotations. The Great Wall of Wan Li has stood on the land of China for thousands of years. From the Great Wall now, we can see many historical vicissitudes and ancient cultural values. Among them, there are many touching stories about the Great Wall. It can be said that the Great Wall is the witness of China's history and the crystallization of the wisdom of the ancient working people in China. Many times, art carries rich cultural connotations and gives people a lot of imagination. At this time, people see not only the cold wall, but also the history. More vicissitudes. To sum up, the Great Wall of China is incomparable to other Great Walls in the world in appearance, structure, scale and use. The Great Wall bears rich cultural connotations and shows the characteristics of ancient architectural art in China. Browse the general situation, geographical location, appearance and structural features of the Great Wall in Wan Li, and how to build the Great Wall in Wan Li, represented by the Great Wall in Qin and Han Dynasties and the Great Wall in Ming Dynasty. Starting from Yumenguan, Gansu, along the north side of Hexi Corridor, eastward along the junction of desert and loess plateau, and then along the interlaced zone between Inner Mongolia Plateau and northern Hebei, it winds on the back of Yanshan Mountain and Taihang Mountain, and turns with the mountain to reach the edge of the sea. Its southeast is dominated by plains and hills. Except the Loess Plateau, most of them are plains below 200 meters above sea level and hills below 500 meters above sea level. The terrain is flat and open, and the cultivated land is concentrated. There are Alashan Plateau, Inner Mongolia Plateau and Daxinganling Mountains in the north from west to east, and most of them are above 1000 meters above sea level, which is the largest and most concentrated area of natural grassland in China. Most of the areas where the Great Wall is located are hills that transition from plateau to plain. Low mountain area. The layout of the Great Wall was chosen in this transitional terrain, on the one hand, because the mountains that were not very steep were always valued in ancient wars. When the productivity level is low and the infantry and cavalry are fighting on their own, natural disasters such as rivers and mountains can be used as an important part of the defense system without the need to build military facilities. Moreover, it was difficult to build a large-scale city wall on a steep mountain with the means of transportation, material sources and technical level at that time. Therefore, the layout of the early ancient war defense system mainly used natural facilities. Only a few sections of the Great Wall of each generation are really built on high mountains. The Great Wall in the Warring States Period, the Great Wall in the Qin and Han Dynasties, the Great Wall in the Jin Dynasty and the Great Wall in the Ming Dynasty almost all made use of the transition surface from the plateau to the plain, which is dominated by low mountains and hills. On the other hand, the terrain transition zone is often characterized by the fact that the absolute height of the terrain is not necessarily high, but the relative height difference is large, and the terrain is rugged and changeable, which is an excellent position for both offensive and defensive. Especially in the middle and eastern sections of the Great Wall Belt in the north. The middle part includes Ningxia, Inner Mongolia, Shaanxi, western Shanxi and other provinces. Due to the strong crustal movement during the geological period, a series of border mountains such as Helan Mountain, Langshan Mountain and Daqingshan Mountain were formed between the Mongolian Plateau and the Loess Plateau. The mountains are asymmetrical, gentle in the north and steep in the south. The eastern part of the Great Wall Belt, including the present northern Shanxi, Hebei, Liaoning and eastern Inner Mongolia, is in the transition zone from the Inner Mongolia Plateau to the Northeast and North China Plain. The main mountain ranges are Yanshan Mountain, Taihang Mountain, Daxing 'anling Mountain, Changbai Mountain, Liaodong Mountain and Western Liaoning Hill. Because of the crustal movement, the mountainous area has been uplifted many times, and the two terraces are relatively high and the terrain is steep. The Inner Mongolia Plateau in the north of the Great Wall Belt is flat, with no mountains, only rolling hills and mounds. South of the Great Wall is the endless North China Plain. Indeed, the desert in the north is vast and the land in the south is fertile. The rugged transition zone in the middle is of course the best military base for ambush, observation and throat control. Water condition is a very sensitive environmental factor in this region, which directly affects the survival of regional people and animals and the development of regional economy. Except that the eastern and western ends of the Great Wall are located in semi-humid and arid areas respectively, most of the sections are located in semi-arid climate areas where the semi-humid climate changes to arid climate areas in China, which forms the staggered distribution of agriculture and animal husbandry in the agricultural production of the Great Wall, leading to frequent fluctuations in the boundary space of agriculture and animal husbandry. The Great Wall is an important dividing line between farming and pastoral areas in China. The position of the Great Wall in ancient Qin and Han Dynasties is roughly the same as the dividing line between agriculture and animal husbandry in northern China today. South of the line is an agricultural area dominated by farming in China; To the north of the line is the grassland area in northern China. From the Warring States to the Qin and Han Dynasties, the position of the Great Wall moved north and west with the expansion of agricultural areas to the north and west. During the Warring States Period, the agricultural area of China was limited to the Central Plains with the Yellow River as the center. There are Taiyuan and Zhongshan in the north, the sea in the east and Xining in the west. Its northern part includes Tianshui, Anding, Beidi, Shang Jun and Hexi Corridor, all of which belong to animal husbandry economic zone. At that time, the Loess Plateau was still a forest grassland. In order to prevent the northern nomads from invading the central region, Qin, Zhao and Yan Dou built the Great Wall on the edge of the agricultural area at that time. During the Warring States Period, Qin Changcheng built the Great Wall to defend the Guanzhong Plain centered on Xianyang. It runs from Lintao, Gansu to the east, passes through Guyuan, Ningxia, reaches Huanxian in the north, Yulin in northern Shaanxi, then turns to the northeast and ends on the west bank of the Yellow River. This section of the Great Wall was generally the western section of the dividing line between agriculture and animal husbandry at that time; The Great Wall in northern Zhao is an agricultural area centered on the capital Handan. The North Great Wall was built from Xuanhua, Hebei Province to the southwest along Sanggan River, to Hengshan Yanshan Mountain, and then to Yinshan Mountain in the northwest, ending in Gaoque. The Great Wall of Yanbei is an agricultural area centered on the thistle of Guodu, which is distributed in Zhangjiakou-Chifeng-Liaohe-Dandong today. The Great Wall of Yanzhao was roughly the same as the middle and eastern part of the dividing line between agriculture and animal husbandry at that time. After Qin Shihuang unified China, the former Yan, Zhao and Qin Changcheng were consolidated and repaired in the north and east. At the same time, with the large-scale reclamation, the agricultural area expanded to the western Hetao area, and a section of the Great Wall was built from the Hetao area of Inner Mongolia to Lanzhou, Gansu Province through the foothills of Helan Mountain in Ningxia. Later, the expansion of the Great Wall in the Western Han Dynasty was also focused on the west. The Great Wall in Hexi Corridor was built to defend the newly expanded fertile Qingzhou planting industry, such as Jiuquan, Zhangye and Wuwei, and also to defend the Silk Road, the main traffic artery to the west. So far, this section of the Great Wall is roughly consistent with the current dividing line between agriculture and animal husbandry. The Great Wall of Ming Dynasty was mainly built to defend the Mongols in the north. Due to the change of the strength contrast between the two sides, the location of the Ming Great Wall was withdrawn from the south, and it was larger than the Great Wall of Qin and Han Dynasties.