For Li Wentian's praise, Ludendorff was very happy.

However, the smile on Ludendorff's face flashed for a moment, and then he frowned slightly, and said with regret: "It's just that time is still too little, the upcoming attack of the Soviet army has disrupted the progress of my project, and many necessary defensive facilities have no time to do, which will have a great impact on the defensive effect of these fortress groups." Now only 70 percent of the entire project has been completed, which greatly reduces the functionality of the entire defense project. ”

Ludendorff spread his hands and said helplessly: "It would be nice if there was another half a year." ”

There were two reasons for the construction of the fortifications in North Cullen: one was the impending Soviet invasion; The other is the climate of Northern Mongolia. It's just that these two reasons are not something that he Li Wentian can change.

However, fortunately, Song Zhewu creatively proposed the construction of artificial underground tunnels.

After carefully studying Song Zhewu's plan and design and construction points for the underground tunnel, Ludendorff and his team agreed that although such a tunnel was simple and quick to construct, it was very defensive, and could not only protect the safety of the infantry well, but also effectively kill and injure enemy soldiers. Even after the enemy occupies ground positions, the defensive forces can still be preserved underground for a certain period of time.

If we can build a large number of such tunnels in conjunction with the original defensive facilities on several fortress groups and around Kulen before the Soviet attack, we can quickly make up for the lack of fortifications that have not had time to be completed. This was a great relief to Ludendorff, who was worried that several fortress groups would not be completed before the war.

The construction of these tunnels is very simple, as long as there is wood, and there is no need for reinforced concrete, which of course requires a lot of manpower.

However, the most important thing in Kulen now is people, not only tens of thousands of engineers have been working in Kulen, but now in order to seize time, except for a few troops left on guard, all the other troops of Kulen have been engaged in the work of building fortifications. At present, the underground tunnel system is 80% complete.

The three fortress groups were built against the hills, and the fire support points in each section were made of reinforced reinforced concrete, which was no problem unless the heavy artillery hit the same point twice. The only thing that could pose a threat to the concrete fortifications of these fire support points was that more than 500 kg of aerial bombs hit the top, or Soviet large-caliber siege mortars hit directly, or Soviet tanks approached and fired shells directly into the firing holes of the fire points, killing and injuring the personnel inside.

However, it is difficult for tanks to shoot at close range.

First, in the mountains in front of all fire support points, blasting or excavation methods were used to create anti-tank slopes or anti-tank trenches, as well as to set up many anti-tank obstacles, which made it impossible for tanks to find suitable firing positions within 500 meters in front of these fire points, and it was even more difficult to aim at shooting holes with a width of only 300 to 400 mm 500 meters away.

And these large fire support points are equipped with anti-tank guns, and Soviet tanks will be impatient to calmly aim and shoot in front of these fire points.

The underground and semi-covered fortification network composed of these large and medium-sized fire support points with tunnels, ditches and trenches are all built along the mountain, and each fortress group forms three complete fire defense circles, and inside and outside these three defense circles, there are also some functional reading defense systems built according to the topography, and to a certain extent, these reading defense systems constitute a strong support for the large defense circles around the fortress groups. In order for the Soviets to finally break through a defensive position, these defensive systems must be uprooted one by one, otherwise the attacking troops will inevitably withstand their heavy firepower.

One of the distinctive features of the fortress group designed by the Germans is that all the fire support points and defensive positions are connected by underground tunnels, through which any position can be reinforced. Unless a position or firing point is completely blown up or occupied, it will never be rendered useless by casualties.

In particular, Ludendorff is most proud of the fact that on the main positions of the No. 1 and No. 3 fortresses, there is a multi-storey reinforced concrete fortress with a wall thickness of 10 meters, in which a 280mm German naval gun is installed. The gun weighs 73.5 tons, fires 600 kg shells, has a muzzle velocity of 815 m/s, a rate of fire of 2.5 rounds per minute, and a firing range of 15 km.

Although these two naval guns were German, Song Zhewu did not buy them from Germany, but from France. This was because after World War I, under the Treaty of Versailles, the Central Powers confiscated it from Germany as an indemnity.

Although these two German naval guns were hugely powerful, they were old guns from World War I after all, and they had long been eliminated in France, which made Song Zhewu pick up a bargain and buy them for only a little more money than buying scrap steel. The only thing that cost more was the 2,000 rounds of 280mm shells and 50 spare barrels.

Since these two huge cannons were installed in the main fortress at the top of the mountain, the firing range was increased again, both exceeding 20 km. The range of the existing artillery of the Soviet Army is within this range, that is, these two naval guns are the killer of all the heavy artillery positions of the Soviet army.

However, their only drawback is obvious, and that is that due to their installation in the hilltop fortress, the firing angle is very limited, and there are about 10km of shooting dead space in the firing range. In other words, although these two naval guns could reach far, they could not attack. However, this would still pose a great threat to the artillery positions of the Soviet troops.

In addition, there are more than a dozen cave-like artillery positions in the recesses of the fortress's defensive circle. These artillery positions, during the bombing and shelling of the Soviet troops, could hide their artillery in holes, and in between the bombing and shelling of the Soviet troops, they could be pulled out to support the defense of the fortress in all directions with artillery fire. For the shelling of some areas, even the artillery does not need to pull out of the hole at all, and only needs to stick the barrel out of the hole to shoot.

"How? Chief of Staff Lee? Now you should be more confident in holding off the Soviet attack. ”

Gao Zongbao glanced at Liang Zhongjia beside him and asked Li Wentian somewhat casually.

For the construction of the three fortresses in Kulun, Gao Zongbao put a lot of thought into it, poured a lot of his efforts, and he was determined to do a beautiful thing in Kulen that would satisfy everyone.

In the past two years, Gao Zongbao has been under great pressure, and he saw that Tao Rong, Li Wentian, Chu Xichun, Zhao Fengwu, Liang Zhongjia, Han Guangdi, and other later people have all been highly valued by Song Zhewu. Among these people, not only Zhao Fengwu, Liang Zhongjia, Han Guangdi, Zhou Yaoming, Wang Bi, Ma Fawu, Pang Bingxun, Jing Yuexiu and others are on an equal footing with him, but also Tao Rong, Li Wentian, Chu Xichun and others are still above him, which makes Gao Zongbao, who was the first to follow Song Zhewu, inevitably feel unconvinced.

(To be continued)