On the west bank of the Yalu River, the Tang army led by Li Shimin slowly arrived here and then camped on the shore. On the opposite side of the river was a tall and steep pass, which was the mouth of the Bogou, the last line of defense in Pyongyang City.

Li Shimin had a habit of fighting, which was that he liked to check the terrain himself, so as soon as the army arrived here, he took Li Xiu, Cheng Yaojin, Li Ji and others out of the camp and came to the Yalu River to look at the mouth of Bogou opposite.

Bogou is actually a valley formed by a broken mountain range. Originally, it was the southernmost branch of the Changbai Mountains. A continuous mountain range was parallel to the Yalu River. However, when it arrived at the Pogoukou, it suddenly seemed to be broken and turned into a valley. Both sides were steep mountains and almost impossible to pass through. The valley was the only passage. So the Goguryeo people built a pass in the valley, namely Bogoukou.

"What do you think?" Li Shimin looked at the opposite side for a long time before suddenly asking the ministers behind him.

"Your Majesty, this entrance of the dou is not easy to fight. Not to mention that the gate is so steep, the Yalu River in front is not easy to pass, because the gate is too close to the river bank, which is equivalent to a natural moat. If we want to attack the gate, we must cross the river. But the other party can give us a fatal blow when we cross the river!" Cheng Yaojin was the first to frown at this time.

"What General Cheng said is that the other gate is too close to the river, and there is no place to camp for our army, so the frontal attack is definitely not possible. The best way is to find a place with a gentle flow to cross the river upstream and downstream of the river. However, the mountains on both sides of the Bogoukou are approaching the riverside, and there is no way to go on both sides, which is troublesome." At this moment, Li Daozong also spoke.

Bogoukou is a valley. Judging from the front of Li Shimin and others, the mountains on both sides of Bogou Valley are in the shape of "eight" and extend to the riverside. There is no way to go on both sides, so there is only one way to cross the river from the front.

Li Xiu was also observing the terrain of Bogoukou at this time. In fact, in his opinion, Bogoukou was more like a river valley. There should have been a river here before that rushing through mountains and then converging to the Yalu River. However, the river water dried up later, a triangular alluvial plain formed, with the mountains on both sides extending to the riverside, and the triangle is Bogoukou. The triangular plain in front is too small, which is very unfavorable for the army to develop formation.

"There is no way to attack head-on. For example, as long as we can build a floating bridge on the river surface and then send troops to defend the bridgehead, we can send troops to the other side continuously. However, the terrain on the opposite side is narrow and the troops sent each time are limited. Therefore, if we want to capture this Pogoukou, we may have to pay a considerable price!" At this moment, Li Ji, who had not spoken, finally said.

"The Goguryeo people on the opposite side will never let us easily build the pontoon bridge, and even if they set it up, they will definitely send troops to destroy it. Just want to guard the pontoon bridge, you will have to pay a lot of casualties. In addition, the casualties at this pass are really heartbreaking!" Li Shimin also frowned at this time. Experienced generals like him can generally estimate the approximate price they have to pay before the war.

"How many troops are there in Bogoukou now?" After a moment, Li Shimin suddenly asked again.

"There were 30,000 troops stationed here, but later it was taken away by Gao Yanshou. However, according to the information sent some time ago, Quanga Suwen seemed to intend to send additional troops to Bogoukou. I don't know how many people are in the city now?" Cheng Yaojin immediately replied at this time. The terrain of Bogoukou was almost impossible to spread. As long as the city gate was closed, the news of the east of the Yalu River could almost not be heard, so they didn't know whether Quanga Suwen sent reinforcements?

"The army rested for two days, and then tested the reaction of the other side in three days. Then you should know how many defenders there are!" Li Shimin immediately ordered that since he did not know the reality of the city, he could only test it with human lives. Although it was cruel, there was no good way.

"Your Majesty, count the time, Su Dingfang's army should also land. Maybe it will attack Pyongyang soon. At that time, maybe it can attack Bogoukou from behind. If it can attack forward and backward, Bogoukou might not be that difficult to attack!" At this moment, Li Xiu suddenly walked forward and spoke.

Li Xiu felt that the cavalry of Su Dingfang could definitely play a key role, but Li Shimin shook his head when he heard his words: "Su Dingfang has only more than 10,000 people, and most of them are cavalry. The order I gave him is to harass Pyongyang as much as possible. At most, it would be to interrupt Pyongyang to transport supplies to Bogoukou. I do not expect them to capture Pyongyang City. The Bogoukou in front of us needs to find a way to solve it."

After hearing Li Shimin say this, Li Xiu remembered that Su Dingfang's subordinates were indeed all cavalry, and siege was indeed not what they were good at. Of course, if a Tang cavalry suddenly appeared around Pyongyang City, and Pyongyang was the richest place in Goguryeo, then you could completely repeat what Su Dingfang did on the Goguryeo border, and even cut off the connection between Pyongyang and the outside world, this was Su Dingfang and their strategic goal.

At that moment, Li Shimin and the others stopped by the Yalu River for a while, and then returned to the camp to rest, but they did not notice that just as they left, there was a person on the top of Bogoukou city looking at them with a telescope. This person was Quangasuwen who had just arrived at Bogoukou.

Quanga Suwen left Pyongyang a few days ago and finally arrived at the entrance of Bogou the day before yesterday. It was a coincidence. After only two days, the Tang army also arrived at the Yalu River, so he immediately climbed up to the city to look at the Tang army opposite the river, but he didn't expect that a group of people came to the river. Although he didn't know Li Shimin, the identities of these people could also be guessed from the behavior of these people. Especially when he saw Li Shimin in the leader, a gleam burst out in his eyes.

"Father, is that person the emperor of the Tang Dynasty?" After Li Shimin and his group left, Quan Nanjian, who was standing next to Quan Gai Suwen, suddenly asked. He also saw that the group of people coming from the opposite side had extraordinary origins, especially the person in the leader, was even more like stars around him. He knew that his status was extremely high at a glance.
Chapter completed!