Therefore, such a thunder fortress, a group of scouts riding on the north side of Yanshan, and the Yanshan defense line formed by the eight dangerous passes at Xifengkou, Gubeikou, Dushikou, Juyongguan, Feihuling, Yanmenguan, and Chenjiagu, which started from Yuguan, was formed.

At the same time, north of the Yanshan defense line, in the area of ​​Shi Tianze's sphere of influence, Shen Mo would also set up a Central Plains Military Region there.

Once the Mongolian army invasion was discovered on the Yanshan defense line, the situation was tight.

The Central Plains Military Region can also send reinforcements to various passes at any time.

In this way, the entire Yanshan defense line was as solid as a sacred. From then on, Shen Mo closed the north gate of the Song Dynasty heavily! ... And Shen Mo also improved many details of the entire defense line, such as the fact that heavy artillery could not be used at Feihukou, but military artillery and stone-cat cannons can be used to defend.

There is also the newly built Thunder Fortress, which has the supply problem during the winter period.

Shen Mo arranged three steam-powered icebreakers on the Lightning River, the lifeline of this Thunder Fortress, and installed artillery on the icebreaker to ensure that the Mongolian army would not block this supply line on the frozen glacier in winter.

At the same time, he was preparing to build a naval military port in Yuguan and where the navy landed.

This military port can transport the supplies and ammunition sent from Tongzhou directly to Yuguan by sea.

Then, by dragging a long row of steam tugs, the baggage was transported to various passes of the Yanshan defense line along the Baigou River, Sanggan River, Gu River and Luan River.

Now, Marshal Jiang Yuxin has set out in advance and is responsible for the construction of Yuguan Military Port.

Jiang Yuxin no longer needed to go to Shen Mo's actions to Xixia, so she was sent by Shen Mo to the military port to inspect and supervise the construction of the military port.

Shen Mo drew more than 10,000 people from his nine field troops and arranged them on the Yanshan defense line as a defensive force.

In addition, a large number of young staff and generals were appointed as guards of the passers-by in various Yanshan defense lines.

Here, Yu Jie and Bu Yucheng, a newly-stooded general, were promoted to the chief and deputy commander of Thunder Fortress after intensive training by their senior Li Muyuan.

Yu Jie, who is the official here, has a broad vision and a big picture concept. Bu Yucheng is the deputy general... Bu Yucheng is now so happy! Because the strategy of the Thunder Fortress has been brewing in his mind for a long time.

Now his idea coincides with the commander, and the commander also built the Thunder Fortress many times stronger than he imagined! In the words of later generations, this feeling was like a boy who wanted to get a car model, but in the end he got a real 550-horse GTR road war god... and he himself was one of the commanders of the fortress! At this time, the ecstasy in Bu Yucheng's heart really made him explode!... In the middle of January of the New Year, Shen Mo's actions in the Sixteen Prefectures of Yanyun were basically completed.

During this period, there were also many young staff members in Shen Mo's staff, who put forward constructive opinions on the establishment of Yanshan defense line. Of course, Shen Mo also adopted the relatively excellent plans of their ideas.

However, there are also many people who oppose the Yanshan defense line set up by the commander.

These passionate young people insist on thinking that offense is the best defense.

Therefore, they were not interested in the guard plan of the Yanshan defense line, but were determined to plan an attack plan for a large army to continue northward into the grassland.

However, Shen Mo quickly gave up this idea through a discussion.

At that time, Shen Mo said to the children: "Observation is the best defense, which is indeed true, but it is not necessarily appropriate to use it in Yanshan at this stage."

"The first problem is that I still have a major matter in the country that has not been resolved.

It is not a wise decision to throw everything away and run to the grassland before completely solving the Song Dynasty.”

Shen Mo's words at this time made the entire conference room silent.

At this moment, many young people here realized that the days when the Song Dynasty dragged their backs on their teachers, stumbling and framed them was finally over! At this moment, many of these staff officers, Zhang Nianqing's faces turned red.

Then he saw the commander and continued, "The second is that I have already eaten too much territory in one bite by leading the army to the Northern Expedition."

"The former land of the Jin Kingdom here has been ruled by the Jin people for a hundred years.

The Central Plains area has also been in the hands of the Mongols for nearly twenty years.

In other words, there has been a generation of young people who have become accustomed to being under the rule of alien races.

For them, perhaps they are not happy to be rescued now, and they are still feeling sad and lost because the country is destroyed."

"This is actually very normal, but it takes us a lot of time and energy to turn them into the people of the Song Dynasty and make them proud of being a Song Dynasty person."

"In addition, we are about to take over the entire Xixia territory... This is another large area of ​​land, and the people living on it are all Dangxiang people."

"So what we need to do most now is actually the digestion of the results, making these places a solid back.

This newly added vast territory is backed by the Tongzhou Army.

The area of ​​these places is too large."

"If the civil affairs of these places are not sorted out clearly and the people have not truly returned to the Song Dynasty, we will rush forward and will taste the consequences of being greedy and not being able to chew too much."

When he said this, Shen Mo smiled and said, "What's more, the north of Yanshan Mountain is full of Mongolian grasslands. If you go north, you will not only have no danger to defend, but will also greatly extend the supply line of the Tongzhou army."

"At least, the supply line at this stage must start from Tongzhou and be stretched to the forefront of the battle."

"But we think about it the other way around, if we digest the entire Central Plains in a few years and manage it into a stable rear.

By then, the starting point of our army northward will not be Tongzhou, but Zhending Prefecture and Hejian Prefecture in the Central Plains, which will greatly shorten the distance of logistics supply!"

"And at that time, our troops will be from the stability of the rear, as well as their economic foundation, number of troops, quality of troops, firepower configuration, and maneuverability, and will be much stronger than they are now, and the Tongzhou Army will definitely be much stronger than it is now!"

"So the safest way to attack north then.

As for now, the establishment of this Yanshan defense line can allow us to leave Mongolia with confidence and concentrate on dealing with the internal affairs of the Song Dynasty. This is enough."
Chapter completed!