The history of Duc is almost the same as the history of other ancient Siberian cities, small granges and castles in the steppe. In 1666 a Russian Cossack tribe moved to the mouth of the Oud River, and in 1690 Verkhniy Udinsk Castle was built. In the 80s of the 17th century, Verkhniy Udinsk was administratively divided into the Irkutsk province, and due to its favorable geographical location on the "trade route" from Russia to China and Mongolia, it quickly developed into one of the main commercial centers in eastern Russia. In 1899, the first train was opened in Verkhniy Udinsk, and the Siberian line of communication connected Verkhniy Udinsk with the interior of Russia, and the city's industry, with mining and metallurgy as its core, began to develop rapidly. After 1900, in order to appease the Buryat Mongols in the Yakutsk province, the Tsarist government renamed Verkhniy Uginsk Ulan-Ude, which means "Red Gate", as a sign of respect for the Tibetan Buddhist lama monasteries in the city - in another time and space, it was not until 19347 at the request of the government of the Socialist Republic of the Mongolian Autonomous Region of Buryatia that the All-Russian Central Executive Committee adopted a resolution on changing the name of the city of Verkhnito Udinsk to Ulan-Ude.

In the Asian-Russian War, the Chinese army once attacked the city of Ulan-Ude, and the million-strong army of both sides confronted each other along the line of the Uda River and the Selenga River.

After the war, in the Siberian defense plan planned by the Russian side, Ulan-Ude was in a very important position, and it was one of the three core places to block the invasion of the Chinese army. In an attempt to reproduce the "glory of the Vladivostok fortress", the Chinese army marching along the Trans-Siberian Railway was firmly dragged under the fortified city, and then turned back and launched a counterattack after the defeat of Germany by the British and French allies.

At the end of 14, the combined East Asian fleet raided Pearl Harbor at the same time as the Chinese army and the Mongolian side. The Front launched a surprise attack on the Russian garrison on the Baikal side from two directions at the same time, and the two mobile assault groups advancing along the Setu valley penetrated into the deep enemy with lightning speed and surrounded Ulan-Ude at the beginning of the following year.

In order to rescue the troops cut off in Ulan-Ude and Chita, and at the same time attempting to take the opportunity to encircle and annihilate the Chinese assault group that was out of touch with the main forces in the rear, the main forces of the Russian Siberian Front assembled on the Irkutsk side launched a counterattack with the support of armored forces, and were routed by the Chinese assault group with more practical weapons and equipment and more advanced combat concepts. Since then, the east of Lake Baikal has been abandoned, and the rest has retreated to the line of the Irkut River.

After the fall of Chita, Ulan-Ude became an isolated city, and the Russian army trapped in the fortress included about 1 division of the remnants of the Siberian Army (the main body was the 7th Siberian Division), the 41st Siberian Brigade was about a brigade, and a garrison regiment of the fortress itself, with nearly 40,000 troops. During the Battle of Ulan-Ude, the defenders once concentrated their forces to assault a corner of the encirclement, trying to join forces with reinforcements and annihilate the besieging Chinese army, but the assault troops > in front of the hill guarded by the 10th "Lion's Roar Regiment". In the end, it was defeated by the Chinese chariots and cavalry that came in time for reinforcements, and more than 8,000 people were killed or wounded. The combat strength was greatly damaged, and the will and ability to attack again were completely lost, and more than 3,000 people were lost in the subsequent battles in the outlying strongholds, and the remnants of the troops relied on the reinforced concrete fortresses and ironclad batteries designed by French experts to hold the fortress defense line. A battalion of 210-mm field mortars rushed over in advance also set fire for test firing >+.

After the preparation for the general attack is completed, we are waiting for the right weather in the air. For a week in a row, I always chose to concentrate on shelling the front line of the Russian army at lunchtime in order to confuse it.

Until 7:30 a.m. local time on the 57th, the morning of Ulan-Ude, which had been silent for a long time, was suddenly broken by the sound of earth-shaking mountains and cannons - like a volcanic eruption. The earth trembled, and the sky burned and discolored!

The large and small caliber guns of all the artillery positions of the Chinese army deployed in the front and depth were fired together, and the dazzling artillery flames reflected the sky above the Chinese positions close to the ground. A huge and indistinguishable roar shook the heavens and the earth, and countless cannonballs pierced the faint morning sky with uneven howls, and from far and near, they swarmed and slammed into the ground like hailstones - followed by undulating explosions, and huge clouds of smoke that swelled in the shape of mushrooms, sometimes rushing up to hundreds of meters in the air, converged into a single area, completely covering the city of Ulan-Ude in the fortress circle.

In the smoke, I saw countless red lights flashing continuously, and the loud sound that was enough to shatter the eardrums was endless, and the Russian soldiers who were exposed to the covering trenches between the fortresses were dazed by this sudden and dense artillery fire, and they hugged their heads and scurried. In the blink of an eye, the bare ground position had been blown up to the ground and cracked, many people were buried alive by the collapsed trench wall, and many more were blown to the ground, and the severed limbs and broken internal organs mixed with dirt and rocks were thrown high into the air, and the air that was rapidly expanding due to the explosion washed over the ground like some kind of rolling liquid, trying to shatter or kick anything that could be shaken!

Even the strong fortress made of reinforced concrete, under the continuous bombardment of dozens of super-large caliber siege guns of the Chinese army, collapsed little by little like disintegrating building blocks, as for those armored batteries with a full texture of steel casting, when directly hit by a 1-ton armor-piercing projectile, it was still like an eggshell poked by chopsticks, and the huge bullets loaded with TNT exploded in the turret, bursting ammunition from time to time, and dazzling fireballs mixed with broken steel pieces and pieces of meat shot out of the bullet holes. Sometimes a turret of tens to hundreds of tons is thrown into the air like a hat!

The Russian soldiers who temporarily survived the position were shocked by the huge roar of rolling thunder, and curled up in all corners, no one dared to raise their heads again, let alone move anymore, everyone was waiting for God's judgment.

In the first few hours, the artillery group of the Chinese army in this direction frantically "sprayed" various shells ranging from 7 kg to 1,500 jin at an average speed of 2 rounds per hour.

Different artillery pieces have different division of labor: 75 mm field rapid-fire guns are mainly used to destroy forward obstacles such as barbed wire and deer, and medium and large-caliber mortars of 120,210 meters are used in 90 and Ben and various heavy grenadiers, and siege guns of more than 305 meters are used for fortresses and batteries to "open the shell" with specially configured concrete destruction shells and armor-piercing shells respectively, and Miganon is used for field artillery deployed by the enemy outside the armored batteries. Long-firing heavy artillery such as 150-meter howitzers are suppressed by firing grenades and special smoke grenades.