Li Zicheng galloped along the left bank of Beichuan, galloping on horseback, running out of thirty or forty miles in one breath, and had already left the auxiliary troops behind, and suddenly blocked the way in front of him by an endless earthen wall.

"Hey, what is this? Is it an earthen city? He slowed down his horse and looked at it carefully, it wasn't like it, such a long city should be a big city, how could he not have heard of it in the history of later generations?

Liu Yunshui also slowed down his horse speed and approached Li Zicheng, "My lord? ”

"Yunshui, what do you see what this is?" Li Zicheng pointed forward with a horsewhip, Liu Yunshui just scratched his head, he was from Ganzhou, and he didn't know what it was, "My lord, ask the local soldiers to see if they know!" ”

During the last Northern Expedition, they also passed through Beichuan County, but at that time they walked to the right bank, maybe there was no earth wall in that section, so they didn't find it, but this time in order to reduce the number of river crossings, they walked on the left bank of Beichuan, and then they found a huge earthen wall in front of them.

After a while, a soldier was brought to Li Zicheng, "My lord, this is a side wall, not a city!" ”

"Sidewall?" Li Zicheng already knew that the Great Wall was only the title of later generations, and in the Ming Dynasty, it also had its own name - the side wall, which was generally located in the frontier, in order to defend the town of the Ming Dynasty, so it was called the "side wall".

The side wall in the northwest direction ends at Jiayuguan and the river pier, and it is impossible to extend to Beichuan, and the direction is not right.

Looking at the mottled earthen wall, Li Zicheng searched hard in his mind, and finally remembered that he had seen it in a certain crossing, called the "West Sea Wall", and according to the title of later generations, it was more accurate to call it "Qinghai Great Wall".

At the time, I thought it was the author's fabrication, but I didn't expect it to be true.

And the side wall here is the acropolis?

Beichuan County is still north of the side wall, and it is set up by itself, it cannot be the target of the side wall arch guard, there is also a Weiyuan County in the east, originally called Weiyuan Fort, from the location point of view, it should be near this side wall, maybe it is stationed on the side wall, but such a military fort, itself is obviously not worth using such a section of the side wall to guard, to build a side wall of this scale, manpower, economic cost is still very high.

Could it be that this side wall is guarding Xining?

It must be like this, except for Xining, there are no important health centers nearby, let alone prefectures and counties.

If the side wall is guarding Xining, the north of the wall should not belong to the Ming Dynasty for a long time, the purpose of the Ming Dynasty to build the side wall is usually to resist the nomads, and the side wall is the dividing line between the Ming and the nomads.

No wonder the Mai Li cadres can swagger and nomadize Dabanshan, it turns out that they have already received the tacit approval of the Ming court!

Since the north of the side wall was not originally the land of the Ming Dynasty, this time the troops were sent to Dabanshan......

Fortunately, before the Ming Dynasty, there were also the Tang Dynasty and the Han Dynasty, as long as you look for it, you will definitely be able to find the connection between this place and the Han people, even if it is a neighbor.

The central country has a vast territory, and the imperial court has never had the vision and habit of expansion, but the Han people have a large population, and in order to relieve the pressure of survival, they will spontaneously expand in all directions and expand their living space.

Even if there is no Han and Datang, Li Zicheng will not stop the Northern Expedition to Dabanshan.

The so-called "inherent territory" is just an excuse to send troops, in the desert land of the northwest, all the nomadic and Han peoples, you sing and I appear, who can say which nation this land belongs to?

Perhaps the first people who owned this land have long been annihilated in the long river of history!

Which nation the land belongs to depends on strength, and the key to the driving force for expanding the land is interests.

The Mai Li cadres went south to Banshan because they valued this pasture, shepherding more livestock for them, and even raising more people.

Li Zicheng's army invaded Dabanshan, on the one hand, to protect the Dadou Pull Valley, connect Xining and Ganzhou with the shortest road, and completely connect the land under his control.

On the other hand, it is still for the copper mine, the Xining army's current demand for copper and iron can be said to be to the point of longing for it, without copper and iron, it is impossible to make Xining rifles and bullets, and it is not easy to find a copper mine, how can Li Zicheng let go?

No matter who Dabanshan's past belongs to, it will have to be controlled by the Xining Army in the future, and even if the Han people have never touched Dabanshan in the past, it is now the turn of the Xining Army.

Feng Shui takes turns, this year to my house!

Since the nomads can't develop this land well, then leave it to the Xining Army!

Not only for the land itself, but also for the copper produced on this land.

"Your Excellency?" Liu Yunshui's words interrupted Li Zicheng's contemplation.

He sneered, climbed the earthen wall with the assistance of the soldiers, and after a visual inspection, the solid platform of the earthen wall was as high as one zhang and five feet, and there was a stomping wall on the wall, which should be more than four feet, and the total height was more than one zhang and nine feet, and even close to two zhang.

The side wall is made of loess and is quite solid, but the section near the river bank is quite badly damaged, probably to facilitate the passage of merchants and people, and this section is almost razed to the ground.

Li Zicheng roughly measured it, and the bottom wall was as thick as one zhang and five feet, which exceeded the wall of the Triangle City, and that is, the top, which was at least seven feet.

"Where does this side wall extend?"

"Lord Hui, this place is called Xiaoshi Mountain, it is said that the side wall extends all the way to the Shaerling of Niangniang Mountain, at least fifty miles, my subordinates just heard about it, and they have not walked this road!"

"Little Rock Mountain? Niangniang Mountain? Sand Ridge? Li Zicheng muttered softly, the side wall is built along the mountain, in line with the Ming Dynasty's habit of building the side wall, if you have time, you might as well walk along this side wall and enjoy the scenery of Niangniang Mountain.

However, now that the army is on the way to the expedition, Li Zicheng does not have this leisure for the time being, and he has no time.

The target of the Xining Army is Dabanshan to the north of the border wall, and it seems that this section of the border wall will no longer be able to play a military role in the future, at most let it be preserved, leaving a period of monuments for future generations, maybe can