Fortified district

A fortified district or fortified region (Russian: Укреплённый район, Укрепрайон, ukreplyonny raion, ukrepraion) in the military terminology of the Soviet Union, is a territory within which a complex system of defense fortifications was engineered.

Each fortified district consisted of a large number of concrete bunkers (pillboxes) armed with machineguns, antitank guns and artillery. The bunkers were built in groups for mutual support, each group forming a centre of resistance. The area in between was filled with various barriers and obstacles, as well as mine fields. A dedicated military unit (Fortified district troops) was permanently assigned to man each region.

The concept of ukrepraions was developed during the Russian Civil War, when large territories were to be defended by relatively sparse military force. The first military units named so appeared in 1923.

In 1928 the program for the construction of the comprehensive system of fortified districts was launched. It started with 13 fortified districts, which over the time have evolved into the Stalin Line.

Beginning in early 1942, long after the fortified lines in the west had fallen, the Red Army began organizing a somewhat different sort of unit, also known as a "Field" Fortified Region (District). These were brigade-sized in terms of manpower (apx. 4,500 men), with anywhere between four to eight machine gun - artillery battalions, a signal company, a medium mortar company, and other supporting units. They were not tied to any fortified line and had some, mostly horse-drawn, mobility, so are sometimes referred to as "field" units, as opposed to the pre-war units, which were static.

"Strong in artillery and machine guns and weak in riflemen, the fortified region was used as an economy of force minor formation for purely defensive tasks such as the holding of passive sectors or the flank of a penetration."

In effect, as Soviet production of heavy weapons vastly increased in the middle part of the war, while manpower was hard put to keep pace, the men of the fortified regions were almost entirely trained as heavy weapon crews, in order to hold ground by firepower rather than by manpower. This was a very practical solution, given that so much of the Soviet-German front was impracticable for offensive action by either side.

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