Chongqing has always been a mountainous city, slender and parallel ridges from the source of Daba Mountain to Chongqing, if you look down from the sky, as if a huge rake raked from the surface, leaving a regular uplift and valley, in the geographical area called the East Sichuan Parallel Ridge Valley, is part of the famous East Sichuan folded terrain.

The 151 support base is in the south bank area, this area is demarcated as the third level of contact buffer zone, the third level of contact is an anti-advent defense operation concept, there are three levels, the first level of contact refers to the probe contact, according to the scope of the Riemann probe, the distance varies from 500 kilometers to 50 kilometers, the second level of contact refers to visual contact, within 50 kilometers and 20 kilometers away, at this distance it is possible for the naked eye to see the Seraph, the third level of contact is physical contact, within 20 kilometers, Physical contact means armed contact, if there is a Seraphic Angel close to this point, then we have to do it - the 151 base is responsible for punching, and it is also the last line of defense of human society, outside the line of defense is no man's land, and inside the line of defense is Chongqing City.

For a long time in the past, 151 held this line.

But it's not actually going to do that.

The next day after Shang Lu came to report, early in the morning, the old man Ji arranged for someone to take him around first, familiarize himself with the environment of the base, and go to the historical memorial hall built at the base, the memorial hall is a simple small bungalow, you can see a row of glass cabinets and a string of old photos hanging on the wall when you enter the door, the operational staff officer and tour guide of the headquarters said that 151 began to design and prepare for it in 2009, and broke ground in the same year, and it was originally envisioned to be a reserve base, which is part of the third-line project in the new century, but no one expected the frontline to collapse so quickly, Before people could react, the front line was pushed to the doorstep, so the reserve became the front line, and 151 went up like this.

This top, up to now.

How many casualties are there? Shang Lu asked.

The tour guide staff pointed to another wall of the memorial hall, which was densely packed with names, a row of fifty or sixty names, and there were four rows.

20% died by angels and 80% by giant machines.

The tour guide staff said.

Shang Lu was taken aback, how could he die more in his own hands than in the hands of the enemy.

The giant machine is as dangerous as the angel, the tour guide staff said, we are five hundred kilometers away from the angel, but only fifty meters away from the giant machine.

He looked at Shang Lu's eyes with a little pity, probably thinking that this was a dizzy stunned young man, and he rushed in in a hurry when he didn't know the situation, such people often died the fastest, he very sincerely suggested that Shang Lu choose a post far away from the giant machine, at least a little farther away from the cave, he said that the thing had a test failed and the pressure relief valve was stuck, and the high-pressure steam leaked at 500 degrees Celsius, sweeping away the entire operation surface, and the nine workers had no life to survive, and the lucky one was broken off his head on the spot, Unfortunately, I struggled in the hospital for half a month.

If you have the ability, go to the joint finger center of Guanyin Bridge, don't come here.

Shang Lu listened, but he definitely didn't expect that Old Man Ji was so satisfied with him that he couldn't let him go.

Coming out of the memorial hall, the tour guide staff led Shang Lu to see the dormitory.

Shang Lu's residence was arranged in a courtyard at the foot of the mountain, which was an office and dormitory of the base headquarters, several gray-white two-story buildings, several offices belonging to the surveying and mapping department, the management department and the direct engineering department, and a small warehouse of the war technology department, the building faced the main urban area of Chongqing in the distance, backed by a verdant ridge, and there were two trees in the courtyard, one was a jujube tree, and the other was also a jujube tree.

"Well, this is the dormitory."

The conditions of the dormitory are similar to those of the automation institute, the moment he pushed the door in, he thought he was back in the institute, a dozen square double rooms, fluorescent lamps hanging from the ceiling, gray-white floor tiles, two single beds, a long table in the middle of the bed, a computer cup on the table, a basin and slippers under the table, someone was already sleeping on one of the beds, people didn't know where they were, the green bedding was stacked together very casually, but I didn't see the legendary tofu block, Shang Luxin said that the organ was a waste of weapons.

His personal belongings had arrived at his lodgings one step ahead of him, and two large woven bags were piled up against the wall.

"Staying in the room with you is Staff Officer Chen Yu from the Operations Section of the Headquarters."

Chen Fish.

Shang Lu memorized the name, hoping that the new roommate would not be secretive, would not grind his teeth, would not sleepwalk, would not smell his feet, would not snore, and would not be interested in men.

"After reading the dormitory, I will take you into the cave, and the chief engineer asked me to take you to him before eleven o'clock at noon, he will take you to familiarize yourself with the maintenance workshop, and take you to eat by the way."

"Is the giant machine in the workshop?"

"Yes, you can see it when you go."

The courtyards and personnel dormitories of the support base are scattered among the mountains, connected by winding paths, seemingly far away from each other in the east and west, but in fact they are just the end of the tentacles of a giant beast hidden underground.

What people on the outside world see with the naked eye is far from what it is.

Anti-advent giant special operations equipment 151 support base is the world's largest tunnel group project, its main body is actually buried in the mountain range of Nanshan, this is an incredible huge project, people spent three years almost hollowed out the entire Nanshan, and stuffed into the ant's nest like a tortuous and complex tunnel, from top to bottom a total of eleven floors, the core of 151 is three giant machinery maintenance workshops and a nuclear reactor, each workshop is 30 floors high.

The tour guide staff said that 151 has a total of 23 entrances and exits, some large enough to drive trucks side by side, and some can only accommodate one person.

One of the entrances and exits is behind the courtyard, quietly hidden between the weeds and shrubs more than one person high, very hidden, only more than one person high, like an air-raid shelter, people who do not know can not notice it within a few steps, but when you go in, you can detect its depth, black hole, I don't know where it leads.

"How deep is this?"

Shang Lu raised his head and asked, the small red light above his head was not visible at a glance.

"Are you asking about the branch or about the total length?"

"Ask both."

"The branch cave is 400 meters, with a total length of 37 kilometers."

Shang Lu touched the cold and rough cement inner wall in the dim light, and the temperature outside was more than 30 degrees, but when he walked two steps into the hole, he felt cold and swishing, and the wind through the hall was whistling, and Shang Lu actually felt a little cold.

"It's also a very sturdy nuclear bunker that can withstand a 1 million ton yield of nuclear weapons exploding overhead, but it's not needed anymore." The staff officer of the tour guide walked ahead, and the voice reflected in the tunnel layer by layer, "Nuclear weapons are completely ineffective against monsters like angels, and these days, nuclear bombs are burned as firewood." ”

The staff officer of the tour guide was obviously well aware of the environment inside the tunnel, and in the dim light, the pace was fast, and Shang Lu trotted all the way.

The further he walked in, the lower the temperature became, Shang Lu could hear the sound of water when he stepped on the ground, and when he reached out, there was a trickle of water flowing down the wall.

"The 151 support base is an organ with a divisional structure, and the department has installed the guard company and the service company and the fire company of the workstation directly under the subordinate team, with a total of more than 1,500 people, most of whom work in the cave warehouse every day." "In addition, there is a monitoring station on a tree, and a company of cars is stationed in the botanical garden......"

The echo of his words suddenly became empty, and Shang Lu raised his head to find that the position of the small red light above his head had increased.

"The hole is getting bigger." Shang Lu said.

"The front is bigger, 151 is the world's largest tunnel project, larger than 153 in the Western Theater, a total of 2.7 million cubic meters of earth and stone were dug up during the construction of 151, if these earth and stone are built into a stone wall one meter high and one meter thick, the length can be 2,700 kilometers, from Chongqing to Changchun." The tour guide staff officer said, "It's here." ”

At the end of the branch was a low, narrow iron door, and from the other side of the door came a cacophony of human voices and the roar of engines.

"This is the 104 main cave, and beyond that is the maintenance workshop of the giant machine, where the chief engineer is waiting for you."

Shang Lu followed and walked over, and his eyes suddenly opened up, and he couldn't help but marvel, under the dazzling headlights, people in various clothes came and went, rows of materials and tools, cars and even excavators were stacked against the wall, tracks were laid on the ground, and trailers honked on the rails. Behind the people, the gray-white concrete cave wall stretched upward, soon beyond Shang Lu's field of vision, forcing him to look up, his gaze following the vertical inner walls on both sides to climb up, and finally converge to form a majestic dome at a height of several tens of meters.

"Like a temple." Shang Lu said.

Later, Shang Lu gave the 104 main cave a nickname, called the 104 Temple.