There are two roads from Hanzhong to Sichuan, one is the Jinniu Road in the west, which is the main line of the ancient Shu Road, also known as Shiniu Road, Wuding Road, Jiange Road, Shu Stack, South Stack. It is a southerly continuation of the Old Road and the Blogging Road. He started from Xingzhou (Luoyang) in the north and entered Sichuan through Jingcang and Jiange Road. The other is the Micang Road, which was called the Dazhu Road in the Song Dynasty, which is the Micang Mountain that passes through the Daba Mountains from Nanzheng in Hanzhong in the north and reaches Bazhou (now Bazhong).

There are five ways to enter Hanzhong from the west or north:

The first is Qishan Road. From Tianshui City through Hui County into the old road (Chen Cang Road) through the immortal pass to Xingzhou.

The second is the old road (Chencang Road, Lianyun Plank Road, Jialing Road) from Chencang to the southwest out of the pass, along the upper reaches of the Jialing River (the old road water) valley road to Feng County, the southwest along the old road water valley, through the present Liangdang (Han Ancient Road), Huixian (Han River Pool) to the current Luoyang (Han Jialing Road) to the water road to Hanzhong, or through the Chenping Road in the territory of the current Luoyang to the present Ningqiang Anyi to connect the Jinniu Road into Sichuan.

The third is the Bao Slope Road: the Bao Slope Road starts from the Baogu Pass in the south (near the Baocheng City in Hanzhong City today), and reaches the Xiegukou (now the Xieyu Pass in Meixian County) in the north, and travels along the Bao Xie's two waters, running through the Bao's two valleys, so it is named.

The fourth is the Meridian Road: from Chang'an to the south into the Meridian Valley, tracing the valley up, through the Fengshui River Valley, tracing the valley south to Guanshi (that is, the Meridian Pass, also known as Shiyang Pass); Cross the main ridge of the Qinling Mountains to Ningshan County, follow the Xunhe River, a tributary of the Hanjiang River, go down through Daxigou, cross the Yuehe Liang to Yueheping, cross the Yuehe River to the south and go along the waist bamboo ditch, cross the waist Zhuling near the ancient mulberry dun and enter the Chihe River, another tributary of the Hanjiang River, go south along the Chihe River, enter Shiquan County through Tielu Town, pass through Wutong Temple to Chihe Town, cross Maling Pass and go around Jiuli Thirteen Bay on the north side of the Hanjiang River to Shiquan County; From Shiquan County to the northwest, through Guyan, around the peak street to Xixiang County Ziwu Town, across the Meridian River into Yang County, through the Chenggu County to reach Hanzhong.

The fifth is Fu Luo Road: the south mouth is located at the mouth of the Fushui River in Yang County, Hanzhong, and the north mouth is located in the West Luoyu of Zhouzhi County. Fu Luo Road is about 240 kilometers long, and it is the fastest and most steep ancient road such as Bao Slope Road, Meridian Road, Lianyun Plank Road, etc. So far, the flight route from Xi'an to Hanzhong has flown along Fu Luo Road.

Xingzhou (now Luoyang County), which is a strategic place to enter Sichuan in the north, is the so-called defense of Sichuan must guard Xingzhou. Luoyang County is located in the upper reaches of the Jialing River, on the southern slope of the western section of the Qinling Mountains. Because of its place as the key to Qinshu and Shaanxi-Gansu, it has been regarded as a place where soldiers must fight and business travel for thousands of years, and is known as the reputation of "throat" and "lock key".

After the defeat of Fuping, the Xingzhou military of the Great Song Dynasty guarding Sichuan made Wu Jue's base camp in Xingzhou (Luoyang).

At the beginning of the third year of Shaoxing, after Yan Sa left the Jingzhou to break the battle of Raofeng Pass, Wu Jue learned the lesson of the last time. Most of the troops from the original garrison of Monk were withdrawn to the area of Lüyang and the forces were reduced. The Song army of Monk Yuan only had about 3,000 people, and he sent his younger brother Wu Zhen to guard Monk Yuan. Last time, Wu Jue only had more than 1,000 people, and he defeated the 100,000-strong army of Jin Wushu with a strong crossbow by risk, and also injured Jin Wushu. This time, the Golden Vulture was still attacking from here, and it was obviously prepared. At that time, it was snowing, and the sentinels of the Song Kingdom were relatively lax. The vanguard of Jin Wushu's subordinates was called Yan Ying, and he offered a plan to Jin Wushu, that is, to take advantage of the slackness of the Song army to send an elite army from the high mountains behind the flank to bypass the Song army's defensive position and attack the Song army, which could receive a surprise effect. The Golden Vulture took Yan Ying's suggestion and sent Yan Ying to lead elite soldiers to carry out a surprise attack.

The monk had already been attacked by the condescending attack of the Jin army, and the camp was in chaos, Wu Zhen knew that a few rounds had been decided, and the Song army could no longer hold on, so he ordered the remnants to retreat and retreat into the follow-up defense line. After the Song army retreated from the monk plain, Dasanguan became an empty camp, and all of them were occupied by the Jin army.

Although there are as many as five roads into Hanzhong in Guanzhong, although the last time Wanyan Sali drank the effect of a sneak attack, but this kind of thing can be done once, done twice, this person has a problem, attacking from the Qinhuai Ancient Road, although the road is slightly better, but there are still many passes and dangers, and the distance is more than a thousand roads, there are too many variables on the road, and the long-distance march also consumes a lot of armament supplies and soldiers' physical strength. Other routes such as the Meridian Road, the Bao Slope Road, and the Fu Luo Road are full of dangers and obstacles, not to mention the plank road, as long as the kapok is pumped, it is enough for you to love. These roads are okay in peacetime, but not in wartime.

Therefore, although the old road is a dangerous road, most of the time it is on the ground, and this down-to-earth feeling is completely different from walking on the plank road. So this time, Jin Wushu chose to attack from the old way, and he wanted to fight with Wu Jue.

Wu Jue only had more than 30,000 troops at this time, and he also had to consider the possibility of Jin soldiers coming east, so he shrank his forces and concentrated on a few major passes to defend, and carried out guerrilla attacks and harassment tactics along the way to delay the consumption of the Jin army.

Wu Jue set up two lines of defense on this old road. One is to follow the old road to block the attack. The other is to stick to the Immortal Pass. Xianrenguan is located at the junction of Luoyang, Shaanxi and Huixian County, Gansu Province, is located on the bank of the Jialing River in the southeast of Huixian County, is near the intersection of Chencang Road and Qishan Road, the left side of the Xianren Yuan, the right side of the Jialing River, the cliffs on both sides of the river, the military supplies are transported to Yuguan along the Jialing River from the rear, and the logistics supply is more convenient. The immortal control guards the Chencang Road and the Qishan Road, and the geographical and strategic location is quite important.

There are two hundred and sixty or seventy miles from the monk yuan to the immortal pass, and the whole passage is either a mountain rock cliff or a river beach and a valley. And the crossbow archers are sent, shooting from top to bottom, the road is narrow, the force can not be spread, although the golden vulture is uncomfortable, there is no way at all, so I have to let the soldiers who run in front of them empty two pieces of armor, when they go up the cliff, everyone uses ropes to connect them so as not to fall into the ravine and river, you think, even if the arrow can't penetrate, the power of the arrow is enough to push you down. Therefore, there is no way to "hook and chain connected, and fish run through" is a method.

In this way, the two sides fought for more than a month, and the Jin army finally reached Tieshan in Hui County.

But this iron mountain is a dangerous pass, Jin Wushu stood in front of the pass and saw that the arrows on it were like flying locusts, and the soldiers could not wear two pieces if they didn't want to, even if they wore three, it was useless, and the soldiers had to be able to walk, and each set of armor was about twenty-five to thirty-five kilograms. Three pieces, to say the least, are one hundred and fifty pounds.

Wan Yan didn't have to see Jin Wushu's brows tightened, and said to Jin Wushu:

"Marshal, such an attack cost the soldiers their lives in vain, and the military strength and arrows behind the Song army were endless. There is no way, I don't know if it will work, it will take time. ”

"Say the solution first, then talk about it if it's good or not, if the method is good, I'll reward you greatly!"

"Look at this Iron Mountain Pass, it is difficult to fly over even if the two mountains are sandwiched."

"I know this, tell me your way." Jin Wushu was a little anxious.

"Look at this side of the mountain, although it is also a high ridge, we can build a road, and cross this ridge is behind the Iron Mountain Pass. You see... ”