The defence line of the Kingdom of Yugoslavia in Carinthia and Styria

In the 1930s, Fascism and especially Nazism threatened to change the borders established after the Great War. Countries therefore prepared for conflict by building defence lines along their borders with hostile neighbours. The Kingdom of Yugoslavia also began building a defence line, first on its western border with Italy, and after the annexation of Austria by Germany in 1938, also in Carinthia and Styria. The paper describes the planning, construction, and wartime operation of the defence line, as well as its integration into the landscape. Apart from examining archival sources and reviewing the existing literature, research also included locating individual fortifications in the field, determining their coordinates, and estimating the remaining portions of Sector 6 in Carinthia and Styria.