From Xiaoguan to Chang'an, there are many checkpoints, fortresses and small cities along the way, if the Shu army attacks all the way to the past, it must be time-consuming and labor-intensive, the key is that after a long time, Cao Pi will know the news of Cao Hong's surrender, and Cao Hong's family will die.

But with Cao Hong's cooperation, it was different, he led two thousand Wei soldiers to take the lead in the front, and he pretended to receive an order from the emperor of Wei to send him to the battlefield on the eastern front, and deceived the city gates and checkpoints along the way. Cao Hong is a marquis, and he is still the emperor's uncle today, although in fact he is not treated by the emperor, but his identity is there, and those guards and guards dare not slack off when they see him.

Basically, as soon as Cao Hong shouted, those people would open the door and welcome them in, but they didn't expect that these "own people" would turn their faces as soon as they entered. As soon as they enter the city or the checkpoint, they will draw ~ a big sword and quickly control strategic places such as city gates, walled gates and beacon towers.

When they encountered the rebels, they were killed, and the Shu army followed closely, and when Cao Hong succeeded, they quickly swarmed in and completely controlled these checkpoints, fortresses and small cities.

Along the way, there was no disadvantage in taking such a method, and soon, they reached the outside of Chang'an City. Cao Hong planned to repeat the old trick again, he led 2,000 people and swaggered to the north gate of Chang'an City, preparing to enter the city from here.

Who knows, when he arrived at the city gate, he found that the city gate was closed, so he raised his head and shouted: "I am happy to wait for the city, I am ordered to enter the city to face the saint, who is the guard, quickly open the city gate!" The title of Cao Hong Hussar General was stripped away by Cao Pi, but the title of Lecheng Hou was reluctantly returned to him by Cao Pi under the interference of Empress Dowager Bian.

But as soon as he finished speaking, a rain of arrows came from the city wall. After all, Cao Hong is a veteran of battle, and his reaction speed is fast enough, and because of the shouting, his head has been tilted up, and his eyes have been staring at the city wall.

I saw him pull out ~ his waist knife with a brush on the ground, shout "retreat", and then quickly turn the horse's head while blocking the arrow with the knife, and run away for his life.

Luckily, he managed to escape the range of the city's bow and arrows with the help of the fast running speed of the horse under his crotch. However, after he escaped, he realized that he had been hit by an arrow in the shoulder. Fortunately, he didn't hit the vital point, so he didn't have to worry about his life, but it hurt him half to death.

His war horse is a little more miserable, three or five arrows inserted in the fart ~ strand, although the flesh of the fart ~ strand is very thick, these arrows are not enough to kill, but he is so seriously injured, he will definitely not be able to ride in the short term.

The soldiers he led were not so lucky, and this sudden rain of arrows took the lives of more than 200 soldiers at once, and countless others were injured.

It turned out that they attacked the city along the way, although they used the method of deceiving the city gate, the speed of the march was very fast, and there were very few enemies who missed each attack, but after all, it was impossible to do not miss a single one.

The army came from the north, and because of the barrier of the pass, it was impossible to go around to the south in advance and outflank everyone. This will inevitably lead to the escape of some enemies. So in the end, someone in the Wei army finally ran back to Chang'an in time to report the news.

Before Cao Hong led his troops to the north gate of Chang'an, the defenders of Chang'an had received orders in advance and knew that Cao Hong had committed treason, so the guards of the north gate of Chang'an set up an ambush on the city wall, intending to shoot him to death when Cao Hong came.

But I didn't expect Cao Hongbao's knife to be old, his vigilance was high, and with a little luck, he escaped from his birth, which can be said to be a person who is not as good as heaven.

Cao Hong, who escaped, was in a hurry, regardless of the injuries on his body, and hurriedly rushed to Zhang Bao's handsome tent, asking Zhang Bao to attack the city quickly and take Chang'an City as soon as possible.

It's not that he is loyal to Shu Han and how much he thinks about Shu Han, but he is worried that his family who is still in Chang'an City will be persecuted by Cao Pi. Judging from the reaction of the defenders at the North Gate, it is certain that his identity has been exposed~ revealed.

Cao Pi must have known that he surrendered to Shu, and whoever was replaced as the emperor could not be polite to the traitorous ministers, and it was inevitable to destroy the family.

However, Zhang Bao didn't care about his request at all, and had no intention of attacking the city. He stationed the main force of the army outside the north gate of Chang'an, and the other city gates were only symbolically guarded by a small number of troops, which was called the siege of the city.

That is to say, if the Wei army in the city wanted to break through from any gate except the north gate, it would be an easy task. This is tantamount to the circumference of the variant.

It's not that Zhang Bao doesn't want to storm Chang'an, it's not that he doesn't want to besiege Chang'an, it's that he doesn't have enough troops at hand. The method of using soldiers, ten is to surround it, five is to attack it, and the enemy can be divided, if it is less, it can be escaped, and if it is not, it can be avoided.

This is the basic principle of using troops, to besiege the city requires ten times the enemy's troops, especially for a big city like Chang'an, the number of troops is too small to scatter everywhere may not even bubble up.

Of course, the troop strength mentioned here is actually more accurately described by the comparison of combat effectiveness. Because of the application of new weapons, the Shu army did not have so many people in many cases, but its combat effectiveness was ten times that of the enemy, and it could still implement an encirclement strategy.

Zhang Bao now barely has an army of 80,000, of which 50,000 are Xianbei cavalry, these people are first-class in the field, but the siege is the last, expecting them to attack the city is to attack the enemy's length with their own shortcomings, very unwise.

In addition, there are 5,000 surrendered troops, that is, Cao Hong's subordinates, these people have just surrendered, and many of their families are still in Chang'an, so they have no loyalty at all, as long as they don't come out to make trouble, they will have to chant Amitabha, let alone expect them to help attack the city.

Not only could these troops not help, but they also had to find someone to watch them and prevent them from defecting. Zhang Bao transferred a thousand-man team from the Xianbei cavalry to be stationed near these surrendered troops, just in case.

The remaining about 20,000 people are the soldiers of the first division, that is, the strength of the two reinforced brigades, which is the main force of the Northern Route Army, they have firearms and first-class attack power, but unfortunately this time they marched all the way with horses, and they did not carry many heavy weapons, which affected their combat effectiveness.

Keqiu still brought dozens of doors to kill them, but unfortunately there were not many rockets, and Zhang Bao planned to use them at a critical time, and he was reluctant to waste them on the siege.

Chang'an City is the ancient capital of several dynasties, after the operation of the dynasties, the city here is high and thick, the fortress is tight, it can be said that it is impregnable. Moreover, Chang'an City has as many as ten city gates, and if the Shu army wants to divide its troops into ten city gates, each city gate can only be divided into a few thousand people.

And the defenders in Chang'an City are more than 100,000 people, if the Wei army is determined to choose a city gate to break through, with more than 100,000 people to impact thousands of people, even if the Shu army is an all-firearms force, it may not be able to stop it, not to mention that most of the North Route Army is now Xianbei cavalry.

Greedy and chewy, even if Zhang Bao wanted to take care of all the city gates, it was impossible to trap the Wei army, and it was easy to be broken by each one, so he simply concentrated his troops together, and the other city gates only symbolically put a small number of troops as a guard and reconnaissance.

After arranging the troops, Zhang Bao had people shoot a letter of persuasion to surrender into the city, and invited Cao Pi to join the Shu Han camp. It is not an easy thing to persuade a high emperor to surrender, but Zhang Bao did it.