Most of the venues reffered to as the Eagles' Nests were built during the reign of Casimir III the Great. The castles were to guard the border of the Polish Kingdom and its capital, Kraków, mainly from a Czech invasion from the side of Silesia. Nowadays, most of the fortresses are in ruins. The idea to mark a route of main attractions of the Kraków-Częstochowa Uplan first came from Stanisław Leszczycki in the Interwar Period. Then a design of a route from Kraków to Częstochowa, similar to the current one, was introduced by a known tourism promoter prof. Kazimierz Sosnowski after WW II.
