Czechoslovak border fortifications

The Czechoslovak government built a system of border fortifications, as well as some fortified defensive lines inland, from 1935 to 1938 as a defensive countermeasure against the rising threat of Nazi Germany. The objective of the fortifications was to prevent the taking of key areas by an enemy (not only Germany but also Hungary and Poland) by means of a sudden attack before the mobilization of the Czechoslovak army could be completed, and to enable effective defense until allies (Britain and France and possibly the Soviet Union) could help.

With the rise of Hitler and his demands for unification of German minorities (the Sudeten Germans) and return of other claimed territories (the Sudetenland), the alarmed Czechoslovak leadership began defensive plans. While some basic defensive structures were built early on, it was not until after conferences with French military on their design that a full scale effort began.

A change in the design philosophy was noticeable in the "pillboxes" and larger blockhouses similar to the French Maginot line when the massive construction program began in 1936. The original plan was to have the first stage of construction finished in 1941-42, whilst the full system should have been completed by the early 1950s.

Construction was very rapid, and by the time of the Munich Agreement in September 1938 there were completed in total 264 heavy blockhouses (small forts or elements of strongholds) and 10,014 light pillboxes which means about 20% of the heavy objects and 70% of the light objects. Moreover, many other objects were near completion and would have been functional at least as shelters despite missing certain heavy armaments in some structures.

After the German occupation of Czechoslovakia border regions as a result of the "Sudeten crisis", the Germans used these objects to test and develop new weapons and tactics, plan, and practise the attacks eventually used against the Maginot Line and Belgium's forts (the most notable is Fort Eben-Emael), resulting in astounding success. After the fall of Belgium, France and the low countries, the Germans began to dismantle the "Beneš Wall", blowing up the cupolas, or removing them and the cannon/MG embrasures, some of which were eventually installed in the Atlantic Wall against the Allies.

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