Of course, this is for the past.

In the past, Qinhangu Pass was surrounded by Gaoyuan in the west, Juejian in the east, Qinling Mountains in the south, and the Yellow River in the north.

There are dense forests on the high plateau, which are difficult for monkeys to climb.

The big river to the north is turbulent and impassable to ships.

Only the rugged and dangerous road in the middle is feasible.

In front of the pass hidden in the valley, there is a deep gorge that serves as a natural moat.

It can be said that one man can stand the test, and ten thousand people cannot stop it.

However, by the middle and late period of the Later Han Dynasty, the dense forests on the plateau had been cut down almost completely, and their role in blocking the army was greatly reduced.

The most terrible thing is that in the middle and late Later Han Dynasty, the Little Ice Age began, and the climate gradually became abnormal.

To the north of Hangu Pass, the water level of the large river, which was originally a natural barrier, was cut downwards, exposing a large area of ​​the river bed.

The army can bypass the pass directly from the flat river bed.

Therefore, Hangu Pass has lost its role.

Today's Tongguan is basically a shrunken version of Qinhangu Pass before the river cut through it.

The reason why it is a shortened version is because the north of Tongguan Pass is the same as Qinhangu Pass, although there is a big river as a natural barrier.

But the south side is not an unclimbable cliff, but a continuous strip of high plateau.

As a result, if you want to defend Tongguan, you need to deploy a lot of troops on the high plateau to prevent the enemy from sneaking up from different positions.

It is slightly inferior to Hangu Pass in the Qin Dynasty.

However, although Qinhangu Pass has lost its role as a dangerous pass, it can still be used as a forward location for garrisoning troops.

Wei State, or Sima Yi, used it as a line of defense to prevent the Han from marching from Guanzhong to Guandong.

On weekdays, the Wei army was stationed in Hangu Pass. When the Han army came, they set up camp on the exposed riverbed in advance to block the Han army from advancing further.

The exposed riverbed is wide enough for caravan travelers.

But as a battlefield, it is a bit small.

During a frontal attack, all troops cannot be deployed.

We don't expect to be able to stop the Han army's eastward advance, but as long as we can delay it for a while and let Luoyang prepare, it will be considered a success.

As the two men guarding Tongguan and facing Hangu Pass from a distance, Jiang and Liu naturally knew the situation of Hangu Pass.

After hearing Feng Duhu's instructions, the two of them couldn't help but be a little surprised.

Jiang Wei couldn't help but said:

"The Central Protector, the Wei thieves are at Hangu Pass. I'm afraid they have been prepared for it. With the strength of the two of us, even if we capture Hangu Pass, I'm afraid we won't be able to go straight to Luoyang."

When Feng Duhu heard this, he couldn't help showing a somewhat surprised look on his face. He looked at Jiang Wei:

Go straight to Luoyang, how dare you think about it!

Who is Sima Yi?

How could it be possible to leave such a big hole?

Not to mention the section from Qinhan Valley Pass to Hanhan Valley Pass, there are still city passes such as Shaanxi County, Lianchi, and Xin'an, all of which can garrison troops.

Sima Yi is an old tortoise, which can be seen from the hedgehog-like defense he arranged in the pass.

If it weren't for the Liangzhou Iron Cavalry led by Feng Duhu, which was a transcendent generation of cavalry, they could have detoured from Liangzhou to merge with the state and penetrate directly into Sima Yi's back.

It is still unknown how long the Battle of Guanzhong will last and how many soldiers will be sacrificed.

The road from Chang'an out of Tongguan to Luoyang is mostly rugged and dangerous. How could Sima Yi let the Han drive straight through?

If we really want to fight all the way through, let alone how long it will take. Even with the current strength of the Han Dynasty, I am afraid it will take a whole country to get through the ancient Weihan Road.

It does not mean that the large river waterway between Tongguan and Luoyang cannot be used.

Emperor Xiaowu of the former Han Dynasty dug the Guanzhong Cao Canal in order to conquer the Xiongnu. A considerable part of the grain transported by the canal was transported from Guandong.

It's just that the efficiency is extremely low and it consumes a lot of people and material resources.

In particular, the section from Hongnong to Shaanxi County (that is, from Lingbao to Sanmenxia) is the most dangerous.

Plank roads need to be dug on the cliffs on both sides of the river, and then trackers can pull the boats along the plank roads with difficulty.

Otherwise, the ship will not be able to sail on the river at all, and will either be swallowed by the turbulent river water, or it will hit the dark rocks in the river and capsize.

Even so, the best situation for the ships transporting grain is still only three or four out of ten, and more than half of them are fed by fish and shrimps in the river.

This kind of transportation method is difficult to sustain for a long time even when the country is strong.

Otherwise, in the later period of Emperor Xiaowu, how could he have caused the tragic situation of "the cities and warehouses are empty, and many people are in exile" and "the world is wasted, and people cannibalize each other."

In the sparsely populated Three Kingdoms era, it was impossible to do such a thing unless it was absolutely necessary.

This is also the reason why Cao Rui wanted to transport the bronze men and dew bearing plates from Chang'an to Luoyang, but was unable to use the river for transportation.

Because at that time, the Wei State was already struggling to support itself in the face of strong pressure from Ji Han. How could there be any spare people's power?

Even if there is civilian power, there is more than half a chance that the boat will capsize in a big river. Only crazy people will use big rivers for transportation.

Although the logistical pressure of Ji Han's army may be easier than that of Wei and Wu at the same time.

But if we want to ensure smooth logistics, we definitely cannot rely solely on the rugged and dangerous path of the Weihan Ancient Road.

After all, we still have to recruit civilians to rebuild the plank roads and work as trackers to pull boats.

If we really do that, we can unify the world.

If Ji Han exhausts his people's power and collapses before he can unify the world, then Adou will be Emperor Yang of the Han Dynasty.

Sima Yi most likely saw this, so he tried his best to capture Shangdang and then control Bingzhou.

He just wanted to prevent Ji Han from imitating Qin's story of destroying the Six Kingdoms.

During the Warring States Period, the Qin State repeatedly sent troops to Guandong from Hangu Pass, but failed to achieve full success.

During the Qin Dynasty, the Qin army did not follow the ancient Weihan Road, but either went south to annex Han from Bingzhou, or went east to destroy Zhao, and then unified the world.

So Sima Yi wanted to force the big man to take the most difficult path!

But Feng Duhu shook his head:

"Bo Yue is determined to attack Luoyang. This is very good. But this time, I don't force you to go straight to Luoyang or anything like that. Just attack Hangu Pass."

"Of course, even if you can't win..."

Feng Duhu pondered for a moment, but finally did not say the second half of the sentence, but instead said:

"No matter what, you can fight as far as you can, fight as hard as you want, the louder the better, I won't interfere."

Having said this, he sat up straight and emphasized his tone:

"If Sima Yi only plans to merge the state, causing Luoyang to be empty, and let you attack all the way and take the opportunity to reach Luoyang City, that would be the best."

However, in Feng Duhu's view, this situation was taken for granted.

Seeing the happy expressions on their faces, he reminded:

"It's just that Sima Yi has a good way of leading an army and is extremely cautious in his actions. In my opinion, he probably won't be so careless."

"So you must remember: do your best, and don't be too reluctant. If there is any discord, retreat to Tongguan immediately. Do you understand?"

Feng Duhu's eyes fell on the two of them:

"If Shangdang has a problem, it can still be saved. But if there is a problem with Tongguan, then the situation will really collapse."

"What happened to Wei Yan can never happen again, do you understand?"

The Central Protector is using Wei Yan's incident to remind himself!

Jiang Wei and Liu Yin were shocked and quickly and solemnly agreed.

When the two were about to leave, Jiang Wei finally couldn't hold back:

"Zhongduhu plans to go to Hedong?"

Feng Duhu yawned and raised the advance document in his hand to cover his face. After yawning, he put down the document and said:

"Yes, when Li Xinhou (Li Qiu) and others arrive, I plan to go to Hedong to meet Sima Yi and his son for a while."

General Guan went to Taiyuan, in the north.

Jiang Wei and Liu Yin went to Hangu, in the south.

Feng Duhu went to Hedong and sat in the middle.

Three ways to go hand in hand.

As Feng Duhu spoke, he narrowed his eyes. He didn't know whether he was tired and wanted to doze off, or whether he was thinking about something.

Sima Yi, I want to see which direction you plan to focus on.

As long as Taiyuan is not lost, everything will be possible.
Chapter completed!