"Invincible Fortresses" is a fascinating historical book that tells about the formation and development of fortresses on the territory of Ukraine. The author examines in detail the architectural features, defense systems and strategic significance of various fortification objects, from the Middle Ages to the present. Particular attention is paid to unique fortresses that played an important role in the military history of Ukraine. This book not only reveals the technical aspects of the construction of defensive structures, but also gives an opportunity to better understand the importance of each fragment of a stone wall or bastion in the history of a people who lived and defended their land. "Invincible fortresses" is an exciting journey into the world of ancient stone monuments that stand as witnesses of time and reveal to us the secrets of past eras.