"Citadel" is a science fiction novel by the famous American writer Algis Budrys. In this exciting work, readers will get acquainted with a unique world where mysterious structures, forgotten technologies and dangerous adventures are intertwined in an exciting plot. The protagonist finds himself at the center of events that force him to make incredible choices and risk everything to achieve his goal. "Citadel" is a book that will captivate readers from the first pages and leave a strong impression long after reading it.