The book is interdisciplinary in nature and is the first of its kind in Bulgarian humanities to provide a comprehensive anthropological study of one of the many Ottoman architectural complexes in Bulgarian lands. The history of the two mosques, the history of their study, and their cultural and historical specificity are the main topics discussed and commented on in the study. Special attention is paid to the buildings belonging to the two mosques that serve religious, educational, and social functions. The study includes a transcript and translation of a document establishing the waqf of Ibrahim Pasha in Razgrad in 1533. This document, called a vakfname, is extremely important because it contains information about the size and boundaries of the waqf, as well as the construction and functioning of the mosque complex attached to it. The significance of the document is also determined by the fact that, for a period of 116 years to date, it is the sixth document of this type to be brought into scientific circulation in Bulgarian humanities. The study includes 22 plans redrawn by architect Yunul Nuriev, as well as 8 drawings made by architect Mümün Mümün.