In 1936-1939 the War of Spain took place, turning its territory into the testing ground of Europe in anticipation of the Second World War; here new weapons were tested: mass media, propaganda and aviation. The national side used Mallorca as “aircraft carrier” from which it launched airstrikes on the Mediterranean coast: a rearguard that required fortification. To defend the cities, the Republican government ordered, in 1937, to build a coastal defensive system (“Mediterranean Wall”).
The Andalusian Defensive Architecture Plan (PADA) justifies the legal protection of all Andalusian defensive architecture based on the historical condition of the region as a border of kingdoms and civilizations. It supports by using the Decree of April 22, 1949 on the protection of Spanish castles; to the subsequent Law 16/1985 on Spanish Historical Heritage, which declared Bien de Interés Cultural the assets included in the Decree of 1949; and extending the term “castle” to the more generic of “defensive architecture” or “military architecture”.
The fortified system executed on the north bank of the Strait of Gibraltar from 1939 pursued two objectives: an offensive one, for which coastal batteries and lighting projectors were installed; and a defensive one, for which around four hundred reinforced concrete bunkers were built for machine guns and / or anti-tank guns along the coastal strip that runs from San Roque to Conil de la Frontera.
During the communist regime of Enver Hoxha, Albania built nearly 200 000 bunkers as a measure of protection towards an imaginary attack from (un)known enemies of the Popular Socialist Republic. Most of these structures built in concrete are still part of the landscapes almost in every part of the territory.