The first day of arrival at the mausoleum was destined to be a sleepless night, and due to the time constraints, the enemy army could arrive at any time, so it was urgent to build a strong fortification. After determining their respective tasks, the whole army immediately threw themselves into the construction of fortifications without resting, and with the concerted efforts of more than 30,000 people, a defensive line was built between Baihu Mountain and Ziyunling overnight.www.biquge.info

The defense line starts from the waist of Ziyunling in the south, extends northeast along the mountain, then turns north to Baihu Mountain to close the entire mountain pass, and then turns west to connect with the Baihu Mountain position. The entire defense line is concave and eight miles long, but if you look closely, this fortification is not as tall as imagined, and it is not made of bricks and stones, but is built of local materials.

The straight city wall of the ramparts, which is also very common, resembles a saw, and there are protrusions on the wall at intervals, like the face of a horse, but it is not a square platform, but a triangular protrusion. There was another identical rampart about twenty paces behind, but slightly higher than the one in front, with the toothed protrusions staggered from the front row.

Needless to say, in the eyes of everyone, such a strange-shaped fortress must have come from the little emperor's 'whimsy', and this is exactly the case, and Zhao Yu's inspiration came from the defense facilities of the Western world hundreds of years later-the fortress. However, the real fortress is not what he made, but a star-shaped fully enclosed fortress, and his current defense system is more like an expanded version of the fortress, which was forcibly straightened by him.

The walls of the earliest Western fortresses were also built tall and reinforced with stone or brick, as were the cities of the earliest Western fortresses, and were equipped with towers or horse faces for additional firepower. If anything, some particularly fortified cities have more than one wall. But with the advent of gunpowder and the development of thermal weapons, such fortresses were no longer suitable for war, and it can be said that artillery gave birth to bastions.

Many of the fortresses are actually civil fortifications, and with ordinary masonry walls, the frontal defense is not much stronger than that of ordinary city walls. In order to prevent damage from enemy artillery fire and to place your own large and medium-sized artillery, low and thick walls were necessary. As a result, the slope of the outer wall of the fortress is only about one zhang high, and if the depth of the trench is subtracted, the part above the surface is only six or seven feet.

Compared with the tall city walls, the fortress is easier to climb, and without hindrance, ordinary people can even climb and traverse with their bare hands without the help of tools; The walls of tall and steep castles, without the aid of tools, or with simple tools, are for the vast majority of people to climb at the risk of their lives, or simply powerless.

However, the Star Bastion was not designed to be a good barrier to the besieging party's climbing, but was designed to give full play to the power of the artillery as the goal - to prevent the besieging party from approaching with firepower, rather than relying on the wall itself. The essence was to change the fortress from a convex polygon to a concave polygon, with star-like angles protruding beyond the defensive line, thus increasing the angle and length of the shot. In addition, from the high city wall to the low moat, although the buildings above the ground behind the city wall are exposed, the safety of the combatants above the city wall is greatly protected, thus improving the overall defense capability.

The central embankment between the two bastions, the wall that connected them, was shorter than in the past, in order to ensure that the rifle range could completely cover the area. The concave fort was built in front of the embankment to prevent the siege artillery from hitting the embankment, and some musketeers were also deployed to strengthen the defense of the trenches. The purpose of building the Triangle Fort is similar, it is only slightly lower than the main fortress, but it can be used to facilitate the artillery on the main fortress to shoot beyond the cannon, and the artillery on the triangular fort also forms part of the crossfire.

In addition, the passage and cantonment shelter hidden between the two platform walls can be used as a cover for the infantry before the counterattack, and in order to prevent the enemy's vertical fire, there are also many horizontal walls between the passages, which can also be bent as needed. The outermost inclined embankment is the place where the crossfire is most intensive, and its angle of inclination helps the defender's firepower to play. In addition, the fortress should be built with brick and stone as much as possible, and even if it had to be used, the outside should be covered with thick soil. Because the soil layer can absorb energy, the masonry is not only easy to damage, but also prone to ricochet, which can lead to serious casualties.

This improvement makes the fortress no dead ends, so that no matter what point is attacked in the castle, the attacker will be exposed to more than one fortress surface, and the defender can use crossfire to perform multiple strikes, which means that any attacked wall can be defended by multiple firepower. The designed multi-layered defense system allows the fortress to form a trench defense network, which can cover the enemy with firepower, turning the defense of the city into trench warfare. Therefore, it can exert a great blocking ability.

The reason why Zhao Yu chose the fortress to build a defense system is that in addition to its ability to give full play to the power of firearms, there are also unavoidable reasons. You must know that the Yuan army suffered enough to attack the city when it went south, so after pacifying Jiangnan, Kublai Khan ordered the city wall of Jiangnan to be demolished, but in the battle, the Song army, which was dominated by infantry troops, needed to be stationed in a certain place for a long time, or when it was necessary to stick to the key points, it was impossible to wait for the enemy to attack every day, so that they would be tired to death without waiting for the battle, so they needed to build fortifications.

You must know that even building a small castle is not something that can be completed in a short time, especially if it is a city that can garrison troops, which is not only too large, but also does not make much sense. Therefore, the defensive power of the front wall of the fortress of the same thickness is not necessarily higher than that of those cities with tall walls, but this defense system is convenient for local materials and rapid prototyping, and the city wall can cover the opponent with multiple layers of firepower, and it is enough to defeat several times or even more than ten times the enemy with a very small number of people.

Of course, there is no such thing as a perfect thing in the world, and the bastion is also flawed. The intricately designed geometric star-shaped fortresses in the offensive and defensive battles of the fortress can usually cope well with the enemy's attack by designing and planning firepower to cover each other. However, the so-called firepower crossover without dead ends is also built on the shape design of the fortress itself. Compared to a city wall or tower, the ability to cope with artillery bombardment has been improved, but this does not mean that it is undamaged after being attacked.

By concentrating on one direction, or by deciding to destroy or blast one of the corners after a protracted bombardment and earthwork, the entire crossfire design will be a dead end. When the fire is lost, the low walls and inclined embankments make it easy for the enemy to cross, and the wide platform gives the defending artillery a good firing platform, which means that the besieging party can deploy more troops at the same time than the narrow wall.

In the case of defenders who are usually inferior in numbers or combat power or firepower, and need to rely on fortifications to balance the gap between the enemy and us, the more troops the enemy can deploy on the attack surface at the same time, the more obvious the defender's disadvantage will be. Therefore, if the Star Fortress loses even the shape of a corner, it will be faced with the only choice left to surrender or be surrendered.

It is precisely because there is no absolute thing in the world that Zhao Yu does not dare to guarantee that this defense system will not be breached, but he is also ninety percent sure that it will not be lost. And his message comes from the fact that the success of the Star Fortress relies on the success of gunpowder weapons, and the attacking side usually has to pay heavy casualties to be able to do it under the premise that both the attacker and the defender use gunpowder weapons at the same time, or the more mature front-loading black powder smoothbore musket and artillery.

But now it is precisely because they have entered the era of hot weapons, and the Yuan army has just glimpsed the door, or mainly cold weapons and equipment, but in the era of cold weapons, it is impossible for bows and crossbows to do things that artillery can accomplish. Therefore, if you want to achieve the status and achievements of the firearms era in the era of cold weapons, the Yuan army is like vainly trying to have the power of a bow and crossbow, which is simply impossible......

Although the fortress has become one of the subjects of city building as early as the training camp of the new army, it has now been gradually extended to the whole army and has become a compulsory training subject, and it has been practiced many times in the exercise, but it is the first time that it has really been put into actual combat, and a large adjustment has been made. Therefore, even though the defense line in front of him had been formed, Zhao Yu still did not dare to be careless, he once again inspected the entire defense line, found the weak points, and urged them to improve it as soon as possible.

"It's already the rainy season, and there are many rivers in the south of the Yangtze River, the groundwater table is very shallow, and the terrain in the valley is high in the west and low in the east. Your garrison hole is dug so low, once it rains, you will have to take a bath! Zhao Yu went down to the traffic trench, drilled into a garrison cave, and inspected Sun Jindao, the commander of the Third Brigade.

"Yes, Your Majesty! I immediately ordered people to rectify and deepen the drains! Sun Jin replied.

"In addition, you see that the soil quality here is not very good, the cantonment cave should be strengthened to support, and the traffic trench should be stabilized with railings and fences as soon as possible to prevent collapse. If the hole collapses the dead, the traffic trench collapses the entire defense line, and there may be a gap! After Zhao Yu came out of the hole, he patted the wall of the trench and said.

"Yes, the subordinates will immediately send troops to protect it!" Sun Jin hesitated and replied.

"What's the difficulty?" Zhao Yu looked at his face with a sad look and asked again.

"Your Majesty...... There is no difficulty, and the subordinates will definitely complete it as soon as possible! Sun Jin replied.

"The big war is coming, it's not the time to talk big with a shy stomach, just talk about it if you have difficulties, don't want your mother-in-law!" Zhao Yu frowned and said.

"Your Majesty, that subordinate is disrespectful!" Sun Jin saluted first, "Your Majesty, this is a mausoleum area, it is strictly forbidden to pick wood and cut wood, we can only look for it outside the valley, this back and forth not only delays time, but also requires a lot of manpower to transport, and the speed is naturally much slower!" ”

"Well, that's true!" Zhao Yu walked up the ladder to the wall and nodded. He knew that this was an unavoidable practical difficulty, and that the construction of fortifications would inevitably require a large amount of timber as support, and the manufacture of war sheds and other protective measures. However, it is impossible to occupy the already precious space on the ship, so it can only be transported from the local materials, and although there are trees all over the mountains, they cannot be harvested, which is really frustrating.

"Commander Zhang, don't you see a good view here?" Zhao Yu stood on the gun emplacement on the wall, looked ahead with a telescope and asked Zhang Pingdao, the commander of the artillery regiment directly under the protection army.

"Your Majesty, yes. The tall trees in front of them not only obscured the observers' view, but also blocked the range of artillery fire, making it difficult to exert its power! Zhang Ping nodded.

"This is not possible, without the support of artillery, it is difficult to support the entire defense line with muskets alone, and the Mongol soldiers jumped directly onto the platform wall without riding horses. You immediately send someone to cut down the trees that affect the observation and clear the shooting boundary! Zhao Yu pondered for a moment and said to Zhang Ping.

"Yes, the subordinates will execute it immediately!" Zhang Ping saluted.

"You're still watching the excitement here!" Zhao Yu turned his face to look at Sun Jindao, who was still crying and mournful, "I'm really angry with you idiots, you watched them cut down trees for firewood, and you didn't send someone to drag them back!" ”

"The subordinates are really stupid, or Your Majesty is considerate......" Sun Jin also understood at this time, and immediately understood what the little emperor meant, and what he said was a move to kill two birds with one stone.

"I didn't say that I would let you cut down trees at will, I just ordered you to clear the shooting realm!" Zhao Yu immediately interrupted his words when he heard this, and waved his hand again and again.

"Your Majesty, isn't this good? When those old men heard this, they not only had to nag and advise, but also cut down the tomb tree, the first emperors would not blame it! At this time, Chen Dun reminded on the side.

"Cut, the living are important, the dead are important? In other words, it's already giving them face, and they still think they can figure it out. Besides, I'm wiping my ancestors' buttocks, otherwise the old nest will have to be cut by those thieves, and it's too late for them to bless me, so why blame? Zhao Yu said disdainfully in the direction of the cemetery.

"Hehe, if Your Majesty's words reach Mr. Deng's ears, what do you think will happen?" Chen Dun nodded after hearing this, and said with a smile. Yesterday, it was obvious that His Majesty asked the gang of thieves to hang up, but the old men gave him a good lecture, saying that his actions were unkind, especially that he should not treat the dying like this, but His Majesty could only carry the pot without saying a word, and he was still indignant in his heart.

"Hehe, do you say that Mr. Deng believes you, or does he believe me? Don't forget that someone's reputation has never been very good when they were in Shuaifu! Zhao Yu smiled, muttered a few words in Chen Dun's ear and walked away with a smile.

"I ...... I'm ......" Chen Dun was choked enough, and he couldn't help but feel angry after thinking about how to refute it for a long time.

"Your Majesty's idea is good, don't dismantle the stage indiscriminately, otherwise don't blame our brothers for turning their faces!" When Chen Dun was on fire, Sun Jin and Zhang Ping suddenly grabbed his arm from left to right and said very seriously.

"I still want to turn my face!" Chen Dun struggled a few times but didn't break away, gritted his teeth and glared, "Do you think that if I hadn't led you to break into the Shuai Mansion back then, you would be where you are today, and now you still have the face to turn against me?" ”

"It was true that you led us into the Marshal's Mansion back then, but later I realized that it was because I was deceived and coerced by you. What kind of place is that Shuaifu, if it weren't for Your Majesty's kindness, we would have been killed on the spot! Sun Jin poked his finger under Chen Dun's ribs.

"Despicable and shameless, I want to break off my friendship with you......" Chen Dun thought that he was really aggrieved, and shouted angrily......