Fortified Area of Silesia

The Fortified Area of Silesia (Polish: Obszar Warowny Śląsk) was a set of Polish fortifications, constructed along the interbellum border of Poland and Germany in the area of then-divided Upper Silesia. It spreads from the village of Przeczyce in the north to the town of Wyry in the south, along the line of sixty kilometers. Headquarters of the area was placed in Chorzów and its commandant was General Jan Jagmin-Sadowski.

As a result of the Plebiscite in Silesia and the Silesian Uprisings, the highly industrialized area of Upper Silesia, which had belonged to the German Empire, was divided between Poland and Germany, leaving Beuthen, Hindenburg and Gleiwitz in Germany and granting both Katowice and Chorzów to Poland.

In the 1920s the Poles did not consider their western neighbor as the main threat, concentrating its defence abilities in the East, along the border with the Soviet Union. However, beginning in the early 1930s, after Adolf Hitler had come to power, the Poles decided to prepare themselves for a war. Upper Silesia was the most important industrial region of the country and its defence was crucial.

Major works on the fortifications did not begin until 1933, when headquarters of the Polish Army decided to take advantage of a proposal provided by General Jozef Zajac, who then was commandant of the 23rd Infantry Division. Zajac suggested that a large number of smaller bunkers should be built, connected with each other by trenches. However, it was decided that nine so-called points of defence would be constructed, each of them made of a few bunkers. These points were:

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