After Zhao Yan retreated to Gubeikou, he immediately transformed and consolidated the Great Wall defense line north of the Sixteen Prefectures of Yanyun. Originally, the Great Wall defense line was used to prevent the nomadic peoples in the north. However, since the Sixteen Prefectures of Yanyun were occupied by the Liao Kingdom, the Great Wall defense line here was transformed by the Liao Kingdom and became their defense line to defend against the Song Kingdom. Of course, this defense line was generally not used, but in order to prevent the Liao Kingdom, it was transformed. Now that the defense line fell into the hands of the Song Kingdom, it naturally needed to be transformed back.

This Great Wall Defense Line is almost the main body of the Ming Great Wall in later generations. Although it is less than ten thousand miles away, its length is still very amazing. Moreover, the Great Walls in some places are already dilapidated. Yelu Renxian drilled from one of the damaged Great Wall Defense Lines and the others. The Song Dynasty did not have the financial resources to repair those damaged Great Walls for the time being, so Zhao Yan could only try his best to use the Great Wall Defense Line that could be used to form a certain defensive force. After all, although the Liao Kingdom seems to have no power to go south now, there is nothing absolute in the world, so Zhao Yan dare not be careless at all.

On this day, Zhao Yan came to a Great Wall defense line more than 20 miles northwest of Gubeikou. The Great Wall here was built during the Northern Qi Dynasty. It had only experienced hundreds of years of storms that caused the Great Wall to collapse. Yelu Renxian was entering the Sixteen Prefectures of Yanyun from this Great Wall. With this lesson, Zhao Yan naturally would not ignore the loopholes in this defense line, so he came to inspect it in person today, intending to temporarily repair the Great Wall, and at least build an available beacon tower, so he would not touch the heartland of the Song Dynasty by the enemy in the future.

"Your Highness, this mountain is located just in the middle of this collapsed Great Wall, and the view is wide enough. You can see most of the area of ​​this Great Wall. In addition, the terrain of this mountain is quite dangerous, and there are springs flowing down the top of the mountain. If we build a beacon tower here, there are about a hundred soldiers stationed in it, it should be a warning!" At this time, Yang Huaiyu pointed to a mountain not far away and said.

Hearing Yang Huaiyu's words, Hu Yanping, Hu Yanqing and other generals also looked at the mountain not far away. Finally, everyone expressed their opinions and their general opinions were similar. They also agreed with Yang Huaiyu's judgment and agreed to build a beacon tower on the mountain.

Zhao Yan has always rarely interrupted such professionalism. After all, professionals such as Yang Huaiyu must be much stronger than his half-tongue. So when he saw that most of the generals agreed, Yu nodded and then took people around the collapsed Great Wall. Among the people they accompanied, there were special people responsible for drawing maps and making sand tables. In the future, the terrain of the entire Sixteen Prefectures of Yanyun will be drawn as maps and sand tables to the capital.

But at this moment, Zhao Yan and others suddenly heard a burst of rapid horse hooves coming from behind. When they turned around, they saw a burst of people running quickly from the road behind them. Fortunately, although the road here is not easy to walk, it is at least much stronger than the mountain road, so horses don’t have to worry about falling into the cliff when they run.

"The soldiers in the army are in front, but the people in the army are not in the army behind. Why do you look so like the eunuch in the palace?" At this time, the sharp-eyed Hu Yanqing suddenly frowned and said. At this time, Zhao Yan and the others also saw that there were several eunuchs in the team of knights, who looked like they were eunuchs in the palace.

Just when Zhao Yan and the others were surprised, the team quickly came to them. When they saw the eunuchs in the team clearly, Zhao Yan was extremely surprised and couldn't help but shout, "Old Huang. Why did you come here?"

Among the eunuchs who came, the leader was Zhao Yan's old acquaintance Huang Wude. After not seeing each other for a few years, the other party looked much older, his hair turned white, and his face was full of wrinkles, but he was in good spirits. He rode on the horse without moving or shaking. It seemed that his health was good, but his back was slightly hunched.

When Huang Wude saw Zhao Yan, he also showed a sincere smile on his face. The wrinkles on his old face were almost smiling into a flower. He immediately jumped off his horse and saluted Zhao Yan and said, "I will meet your highness. Your Majesty sent you to see your highness telling you something important!"

"No need to be polite!" In fact, even if Huang Wude didn't say it, Zhao Yan could guess that the other party was sent by Zhao Xu. It was just that Huang Wude just said that there was something important, but he didn't say what it was. It seemed that it was inconvenient for Yang Huaiyu and others to know. This made Zhao Yan a little curious, so he told Yang Huaiyu and others, and then brought Huang Wude to a small hill next to him. The surroundings were empty and there were guards guarding him below, so there were no need to worry that others would hear their conversation.

Huang Wude took a deep breath at this time, and his face became a little serious: "Report to your Highness, Your Majesty has sent an old slave to send you an oral order, hoping that you can return to the capital early, but Your Majesty is not willing to force you, so if you don't want to go back, Your Majesty will not force you."

When Zhao Yan heard that Zhao Xu had issued such an oral order to himself, he was stunned for a moment. After a while, he said, "Why did my brother ask me to go back? Is something happened in the capital?"

"This..." Huang Wude hesitated for a moment, and then he finally gritted his teeth and said, "Your Highness, Your Majesty did not let Lao Nu tell you about this, but Lao Nu thinks it would be better for you to know about it earlier. Your Majesty was seriously ill before and had not recovered. Instead, it made his condition worse and worse. Now he is unable to attend court. So Your Majesty wants you to go back and help him take charge of the government affairs!"

"What?" Zhao Yan was also shocked when he heard this. He also knew something about Zhao Xu's illness. However, he always thought that Zhao Xu was sick because of anger and was not very serious. In addition, Cao Qi and Zhilu Gu were also in the capital, so he thought that Zhao Xu's illness should have been cured for a long time, but he did not expect that his illness not only did not recover, but became so serious.

"Your Majesty's condition was not very serious. Old God Cao also said that as long as he could calmly recuperate for a period of time, his body could recover, but there were too many things during this period. First, the army that recovered Yan Yun was trapped, and then the Manichaeism and Xixia were in trouble. These things required Your Majesty to drag the sick body to deal with them personally. As a result, the minor illness was dragged into a serious illness. Before leaving the capital, Your Majesty could no longer get out of bed." At this time, Huang Wude added again, and his face also showed a bit of sadness. Zhao Xu was grown up when he watched him grow up, but now Zhao Xu's body is worse than an old man like him.

"Okay, I'll go back soon!" Zhao Yan agreed immediately without thinking that Zhao Xu was not only his elder brother, but also the emperor of the Song Dynasty. Whether it was Yu Gong or Yu Private, Zhao Yan would not let him go, so he had to rush back to the capital as soon as possible.

Next, Zhao Yan immediately took Yang Huaiyu and others back to Gubeikou, arranged the matters in the army for a while, and immediately rushed back to the capital with Hu Yanping and others. However, Huang Wude did not go back with him, but was sent by Zhao Yan to Guangzhou and took Cao Ying and others back to the capital from there, because Zhao Yan estimated that after he returned to the capital this time, he would probably not leave again in a short time.

After leaving Gubeikou with a team of about 2,000 people, Zhao Yan galloped southwest. Because he was worried about Zhao Xu's illness, Zhao Yan almost didn't rest any time along the way. Everyone rode their horses and ran wildly. After half a month of running, he finally arrived at the Yellow River Port in the north of Kaifeng City. As long as he crossed the Yellow River from here, he could reach the capital for a long time.

There are pontoon bridges on the Yellow River, and people from both sides of the north and south can travel through pontoon bridges. There are special officials on the pontoon bridges, and those who cross the bridges need to pay a fee. In addition, because there are too many people crossing the bridges and the number of people crossing the bridges is limited every day, many people are blocked on the shores on both sides of the bridge, waiting to cross the bridges.

As Zhao Yan and the others had no need to rule out the identity. After Zhao Yan's guards revealed their identity, the officials guarding the bridge immediately trotted forward to greet him, and then personally escorted Zhao Yan and the others across the bridge. However, just as Zhao Yan and the others walked across the bridge, the official guarding the bridge was about to say goodbye, but at this moment, Zhao Yan's eyes accidentally swept the fields beside the bridge, but he was stunned for a moment.

"This... these should be sweet potatoes, why are there people growing them here?" Zhao Yan reached out and pointed to the fields beside the bridge, and then asked the official guarding the bridge that after Zhao Yan brought the sweet potatoes and corn to the Song Dynasty, they have only been planted in the military fields in the south. Although Zhao Yan has not been involved in the military affairs in recent years, in his opinion, the cultivation of sweet potatoes and corn should have not been made public yet, otherwise he would not have received any news.

The official guarding the bridge heard Zhao Yan ask about the sweet potatoes in the fields. He looked at Zhao Yan in surprise, and then said: "Your Highness King Yue, these sweet potatoes are said to have come from the south, with amazing yields. As early as last year, people started planting around the capital. There were fewer people planted on the edge of the Yellow River. Among them, no one has planted them north of the Yellow River. However, if you go to the capital, you can see sweet potatoes planted everywhere."

The officials guarding the bridge were too low and they didn't know the relationship between sweet potatoes and Zhao Yan, and they didn't know the meaning of sweet potatoes, so they wondered why Zhao Yan was interested in sweet potatoes. However, when Zhao Yan heard that sweet potatoes had been promoted near the capital, he showed a bit of solemn expression on his face. If this was the case, then the sweet potatoes would soon spread to the north of the Yellow River, or even to the Liao Kingdom, which was not good news for the Song Dynasty.

Before he arrived in the capital, Zhao Yan's mood became a little heavy because of the sweet potatoes. Then after a long time of rushing, the tall and majestic Tokyo City finally appeared in front of him. (To be continued)
Chapter completed!