In this work by Halil Ethem Eldem Bey, which we have prepared for publication, the history and construction process of Yedikule Fortress—the inner citadel of Istanbul that has been the scene of significant events in Turkish history—are discussed in detail, along with its planning. It is known that after the conquest of Istanbul, Fatih Sultan Mehmet repaired the towers remaining from the Byzantine period and added three new ones, naming the structure ‘Yedikule’ (Seven Towers). These are the Flag Tower, Genç Osman Tower, Armory Tower, Treasury Tower, Cannon Tower, Dungeon Tower, and Ahmed III Tower. Some of these towers are described in the text in relation to historical events. Indeed, this fortress with its seven towers, which bore witness to many historical occurrences, served during the Ottoman era as a storage place for numerous precious artifacts, jewels, war equipment, medals, garments, and official documents. However, as their preservation became difficult over time, the aforementioned state treasures were transferred to the palace, and the fortress was converted into a prison and a place of exile. The towers were used as dungeons for a long time, housing statesmen, members of the dynasty, and foreign criminals who were not intended to be executed. Yedikule attracted the attention of European travelers, historians, and artists, and many drawings and engravings of this site have been left behind. In the first edition of this book, which was enriched with numerous visuals, maps, miniatures, and engravings by figures such as Makridi Bey, Mamboury, Melling, Piri Reis, Seyyid Lokman, Wilhelm Delich, Vavassore, G. Ferrario, A. Joanne, Thomas Allom, and Fyodor Uspenski were included. In this new edition, the aforementioned works have been compiled from sources with consideration for print quality, and drawings and engravings by Albert Gabriel, Mary A. Walker, W. H. Bartlett, Choiseul Gouffier, Guillaume Cavelier, Krischen, and Jacob von Sandrart have also been added.