The Great Wall is mainly used for defense, not for ornamentation, so when there is a need for defense, the ruler will be very keen to build the Great Wall, and when there is no need for defense, the ruler will not spend a lot of manpower and material resources to build the Great Wall, this reason is the simplest thing.

In the early days of the establishment of the Tang Empire, because the territory was still relatively small, there were a large number of hostile forces around, especially Liu Wuzhou from the north, this Liu Wuzhou relied on the support of the Turks, and captured Jinyang, the birthplace of the Tang Dynasty, and captured most of the places in Hedong, forming a trend of coercion in Guanzhong, the Tang Dynasty immediately took tough measures, on the one hand, it was natural to send Li Shimin, the king of Qin, to lead elite soldiers and horses to resist Liu Wuzhou, and on the other hand, it was to quickly build defensive facilities, that is, to build a Great Wall to resist the threat of Liu Wuzhou, It can even block the Turkic cavalry that may move south at any time to protect the safety of the nascent Tang regime.

After that, because the territory of the Tang Empire has been expanding, and finally after defeating the strong enemy Turks, the territory has been expanded to a far north, and all the Great Wall in the territory has become an internal defensive structure, and it has lost its military defensive role, so it is not so important.

In this case, the Tang Dynasty did not continue to build the Great Wall, and even, the maintenance of the original Great Wall was canceled, and some of the cities near the Great Wall, in order to build the city wall, would even remove the stones on the Great Wall, and use these stones to build the city and the buildings in the city.

In the Tang Dynasty, there was the Great Wall but it was not used, and when it came to the Great Song Dynasty, there was no Great Wall at all, and the Northern Song Dynasty could still have a little Great Wall to rely on, and when it came to the Southern Song Dynasty, the territory ran along the Huai River, far away from the Great Wall, and there was no problem of repairing the Great Wall.

Although the Great Song Dynasty did not have the Great Wall to build, the Liao State and the Jin State that occupied the Central Plains continued to build the Great Wall, and it also took a lot of energy, and even the Mongolia, a nation on horseback, also started the cause of building the Great Wall after the establishment of the Great Yuan Dynasty.

And when it came to the Ming Dynasty, because of the need to defend against the southward movement of the Mongolian cavalry, so, the Ming court once again carried out a large-scale plan to build the Great Wall, and many tall and majestic Great Wall retained in later generations were built during the Ming Dynasty, and the Great Wall built during this period was better and longer, and it can even be said that the Great Wall of the Ming Dynasty was the most built in all dynasties.

After all, the time of the Qin Dynasty was very short, only a few decades, and the length of the Great Wall that could be built was certainly not as much as that of the Great Wall built by the Ming Dynasty, because the Ming Dynasty had been building the Great Wall for more than 200 years, and it had never stopped.

This is also related to the threat faced by the Ming Dynasty, after driving away the Mongol forces, the unwilling Mongolian nobles Warat and Tatar, often led their troops to the south to harass, causing great harm to the border of the Ming Dynasty, in addition, the newly rising Jurchen tribe in the northeast has become more and more powerful, these forces are relatively strong, and all have strong cavalry, in order to deal with them, the Ming Dynasty had to spend huge manpower and material resources, on the border to build the Great Wall, with the Great Wall to resist the threat of these nomads in the north.

By the time of the Qing Dynasty, due to the great increase in the country's territory again, the northern border has been extended to uninhabited areas, and there is no enemy in the north who can threaten the Qing Dynasty, so the Great Wall is naturally ignored again, at least, the inherited Ming Great Wall is enough, and there is no need to continue to spend huge manpower and material resources to build a new Great Wall. And in the late Qing Dynasty, the main enemies of the Qing Dynasty were from the sea, and it was even more meaningless to build the city wall on land, and with the increasing power of firearms, the city wall built with stone and loess no longer had much substantive effect, and the powerful artillery could easily blast the heavy stone city wall into a big hole, so it was meaningless to continue to spend huge manpower and material resources to build the city wall.

According to the records of later historical documents, the construction of the Great Wall of more than 10,000 miles, that is, the Qin Dynasty, the Han Dynasty, and the Ming Dynasty, the Qin State built the Great Wall from Lintao in the west to Liaodong in the east, the Han Dynasty built the Great Wall from the Hexi Corridor in the west to the east of Liaodong, and the Ming Dynasty built the Great Wall from Jiayuguan in the west to the Yalu River in the east.

The Great Wall that later generations can see and know is the Great Wall built by the Ming Dynasty, such as the famous Badaling Great Wall, which is the essence of the Ming Great Wall.

Li An leaned down casually, pinched it gently, and pinched off a large piece of loess on the Great Wall of Qin, after all, the city wall here has fallen into disrepair, under the intense exposure of the sun, the loess has become very loose, at least the exposed surface loess, it is indeed very loose, as long as it is gently pinched, it will be broken.

"Check it out! The Great Wall here was originally able to resist sword attacks, but now, as long as you pinch it lightly with your hand, it is no wonder that it is almost a thousand years old, and the loess has long been weathered. ”

Ang Lee opened his mouth and sighed.

"In recent years, at the request of my sister, I have also read a lot of history books of the Central Plains, the Great Qin Dynasty unified the world, and made a great contribution to the prosperity of the whole world, and the construction of the Great Wall is a good way to protect the people of the Central Plains, which is a good thing for generations to come, but the Qin Emperor has borne too much infamy."

Li Hanlu opened his mouth and sighed.

"Yes! Emperor Qin did bear too much infamy, but he was not wronged at all, who made him so happy, leaving no room for work, he forcibly conscripted millions of people to build the Great Wall, tired many people, and the harsh government he formulated made future generations tremble when they heard it, and it was normal to be scolded. ”

Li An said.

Qin Shi Huang unified the six countries, built the Great Wall, the same track, the same book, and made a great contribution to the development of Chinese civilization, but he was too impatient to do things, and he wished to do everything in a short time at once, so the situation naturally increased the burden of the people, made the people miserable, and then issued a cry of suffering in the world for a long time.

"Yes! Emperor Qin was too anxious, and in order to build the Great Wall, many people died? I heard that as long as a man dies of exhaustion, then the body will be buried in the Great Wall, is this true? If it were true, it would be terrible. ”

Li Hanlu opened his mouth and said.

Li An nodded and said, "This is naturally true, why don't we dig it up now, maybe we can find some corpses from this section of the city wall ruins?" ”

"Forget it! Or don't dig it. ”

Li Hanlu is not afraid to see dead people, but digging the Great Wall to find corpses is not a fun thing, she is not willing to do such a boring thing.

"By the way, I heard that there is a girl named Meng Jiangnu, she can cry down the Great Wall, I don't know if it's true, if it's true, it's too evil."

Li Hanlu continued to ask.

Ang Lee's question, I don't know how to answer, this kind of thing is obviously unlikely to be true, how can the Great Wall collapse because of a woman crying, unless there is an earthquake, or the quality of the building will collapse.

However, the matter of Meng Jiangnu crying about the Great Wall is still quite interesting.

According to legend, in ancient times, Meng Laohan and Jiang Laohan were neighbors of each other, only separated by a wall. One spring, Meng Laohan planted a gourd seed in his yard, after watering, fertilizing and carefully cultivating, the gourd seedlings grew fat and tall, climbed over the wall, and made a big gourd in Jiang Laohan's yard, weighing dozens of catties. After the gourd is cooked, Jiang Laohan took a knife to cut it, and suddenly saw a white and fat, very cute female doll lying inside, Jiang Laohan was overjoyed, and ran to tell each other, after the people in the village heard about it, they came to watch this new thing, but Meng and Jiang The two old men had a conflict because of this, and they quarreled. Meng Laohan said very firmly: "I planted this gourd myself, and the fat girl should belong to me." Jiang Laohan said stubbornly: "This gourd is knotted in my yard, and this girl should be mine." After arguing for three days and three nights, it was difficult to solve the problem, and there was no result, and then the villagers mediated that the female doll belonged to the two families, took turns to live, and raised together, and took the name of "Meng Jiangnu".

Time is like an arrow, the sun and the moon are like a shuttle, more than ten years have passed in a blink of an eye, and Meng Jiangnu has grown up. One day, when Meng Jiangnu was picking a gourd, she found a person hidden behind the gourd holder. Meng Jiangnu just wanted to call someone, but that person covered her mouth. Later, that person told Meng Jiangnu that his name was Fan Xiliang, and he hid behind the gourd frame in order to avoid the officers and soldiers arresting people to build the Great Wall. After that, Fan Xiliang lived in Meng Jiangnu's house. The so-called long-term love, Fan Xiliang married Meng Jiang's daughter with the consent of Meng Jiang's two parents. On the day of marriage, the groom was taken away by several officials. Fan Xiliang was assigned to serve as a man to build the Great Wall. A year has passed in a blink of an eye, Fan Xiliang has no news, so anxious that Meng Jiangnu can't eat, can't sleep, I don't know what to do, after discussing with the two old people, I decided to go to my husband, swearing that I would never go home if I couldn't find my husband.

She took dry food and special warm clothes for her husband and set out on the road. Along the way, the wind and rain, the sun and the cold, hunger and cold, difficult steps, after a thousand miles of hardships and dangers, she finally found the place to repair the Great Wall, a few people died for the construction of the Great Wall, her husband Fan Xiliang had already died of exhaustion, and was buried under the Great Wall, and the bones could not be found. This news was like a thunderbolt in the sky, Meng Jiangnu immediately cried sadly, tears like springs, sound like thunder, crying earth-shattering, the sky was dark, watching the Great Wall collapse little by little, crying wherever it collapsed, it was eight hundred miles long. This made the director of the project anxious, and hurriedly went to report to Qin Shi Huang, who was here to inspect the progress of the project. Qin Shi Huang hurriedly went to see Meng Jiangnu to ask the root cause. After seeing it, I was fascinated by her beauty, and I had to call her "Zhenggong Niangniang". Although Meng Jiangnu was full of anger, she still suppressed the hatred in her heart, and with a wit, she had to ask Qin Shihuang to agree to her three conditions before she could be the "Zhenggong Niangniang". First, to find the body of her husband Fan Xiliang; second, to hold a state funeral for her husband; Third, Qin Shi Huang was asked to wear linen and filial piety for Fan Xiliang, and to send a flag to the funeral. Qin Shi Huang listened to the three conditions put forward by Meng Jiangnu, thought for a moment, in order to get the beautiful Meng Jiangnu, he agreed to come down, Meng Jiangnu wore filial piety to worship the tomb of Fan Xiliang, who died for the construction of the city, his wish has been fulfilled, facing the rolling Bohai Sea, he jumped and committed suicide by throwing himself into the sea.

Although this story is very fake, it also reflects how angry and resistant the common people at that time were to Qin Shi Huang's forced conscription of millions of laborers to build the Great Wall, and the person who made up this story was also a person who opposed Qin Shi Huang's tyranny and sympathized with the common people.

This story is very popular for the people at the bottom, which reflects the voice of the people at the bottom, thinking that the Great Wall built by Qin Shi Huang with huge manpower and material resources collapsed in an instant, and Qin Shi Huang was played by Meng Jiangnu, the people who heard this story will feel very happy in their hearts, and their hearts will be much more comfortable.

As far as the Great Wall itself is concerned, it is unlikely to collapse, because the Great Wall is very stout, the thickness is five or six meters high, among them, the narrowest at the top is 5.8 meters, and the widest is 6.5 meters, in the case of a total height of about 10 meters, the city wall of such a width can be called extremely stable, as long as there is no strong earthquake, it is absolutely impossible to collapse easily.

The upper surface of the wall was wide enough for two heavy carriages, and the wall was composed of an outer eaves wall and an inner eaves wall, filled with earth and gravel. The eaves wall refers to the side of the outer skin wall facing the outside of the city. When constructing, there is an obvious score, the score is generally 125% of the wall height, the wall can increase the width of the lower part of the wall, enhance the stability of the wall, strengthen its defensive performance, and make the outer wall majestic. The inner eaves wall refers to the outer skin wall in the city, there is generally no obvious score when constructing, and it is constructed into a vertical wall, about the thickness of the outer eaves wall, it is generally based on the thickness of the wall at the "battlement", the thickness here is generally one and a half bricks and a half, according to the proportion of the score, the deeper the thicker, and the masonry method of bricks is mainly flat masonry.

"Meng Jiangnu crying on the Great Wall is a story, of course this can't be true, how can Mrs. believe a small story, do you need to ask this?"

Ang Lee still opened his mouth to explain.

"That's true, and the person who made up the story is really interesting."

Li Hanlu said.

"Look, the beacon tower over here is still there?"

Li An and Li Hanlu walked a few steps on it, and arrived at the position of a beacon tower, which was relatively wide and the ground was flatter.

"This beacon tower is well preserved, and the traces of the female wall are still there."

Li Hanlu opened his mouth and said.

"Does Madame know the role of the beacon?"

Ang Lee asked.

Li Hanlu opened his mouth and replied: "I know, of course I know, the beacon tower is designed to convey the enemy's situation, when it encounters the enemy, it releases smoke during the day and raises fire at night." ”

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