During the Second World War, the Hungarian government built a military defense line in the north-eastern Carpathians – the Arpad Line. It consisted of several belts. The first one is in Prykarpattia, to protect the approaches to the main Carpathian watershed ridge, which was called the Gunyadi line. The second passed along the tops of the main Carpathian ridges and consisted of trenches and dugouts – the so-called line of St. Basil. The third – along narrow river valleys and near large settlements, included concrete fortifications and mechanical obstacles – the Arpad Line.